Sweet Mary Ellison, from Laramie, Wyoming, was introduced to Oakdale life, through her adopted son, Teddy. Teddy was the biological son of Grant Colman and his ex-wife, Joyce Colman. After their separation, Joyce neglected to tell Grant about her pregnancy and placed the boy up for adoption. Joyce didn't tell Grant the truth until a few years later on his wedding day to Lisa Miller Shea. Doubting Joyce's story, Lisa and Grant decided to investigate and found out she was telling the truth. The boy was named Teddy and he was adopted by a working class couple, Mary and her farmer husband Brian Ellison, in Laramie, Wyoming. Deluding herself that she, Grant and Teddy could become a family, Joyce initiated a custody suit against the Ellisons. Although, after he met the boy, Grant formed an attachment to Teddy, he assured Mary and Brian that he would fight Joyce's attempt to take him from them. However, Grant soon found himself in an uphill battle-- his signature had been forged on Teddy's transfer papers, rendering the adoption invalid.

By the beginning of 1976, Mary and Brian were in grave danger of losing custody of Teddy. Joyce was still suing for custody. Grant didn't want his son anywhere near his unstable ex-wife, and, to make matters worse, the custody fight was wreaking havoc on his marriage to Lisa, who had had it up to her ears with Joyce. At the hearing, under questioning by her attorney, Dick Martin, Joyce related how her doctor had badgered her into giving up her child by administering drugs to increase her anxiety and telling her how hard it would be for a single woman like herself to raise a child. Mary came in from Laramie to attend the hearing and Dick did his best to discredit her. The judge, however, maintaining that the bond between loving adoptive parents and their child should not be destroyed, awarded custody to Mary and her husband, Brian. Later, when Brian was killed in a farming accident, Mary moved to Oakdale with Teddy to find a job with Grant's help. Although Lisa liked the young widow, even giving Mary a job temporarily at the Wade Book Shop that she owned, she knew Joyce would never be able to leave Mary and Teddy alone.

Lisa was proven correct. After Joyce was turned down by Bob, Joyce turned to Bob's older brother, and Grant's colleague, attorney Don Hughes and eventually they got engaged. Lisa schemed to break up Joyce and Don, by playing matchmaker and fix up Mary and Don, so she invited Don to dinner but forgot to tell him about Mary. When Don saw Mary he realized Joyce was right about Lisa and Grant wanting to break them up, and he ripped into Grant, who was also there, and stormed out of the house. A little while later, Mary approached Don to try to find out if he was angry at her. Don said he was not and then agreed to hire Mary as his full-time secretary at Lowell, Hughes & Colman. When Joyce found out that Don had hired Mary, she was furious and felt Don had hired Mary out of spite! One day at Memorial Hospital, while Mary was delivering some legal documents for Don, Joyce cornered Mary and told her in no uncertain terms to lay off of her man. Joyce decided it was time to put pressure on Donald and get him to marry her. When she told him she loved him and reminded him of the open ended engagement, he replied that he was still "finding himself" and wasn't ready for the commitment of marriage. Joyce showed Donald the door and told him to come back when he was more certain of his feelings. Until then, she wanted nothing to do with him and broke off the engagement! Don got a temporary job through his father, senior partner, Chris Hughes, in Switzerland.

In early 1978, Don returned to Oakdale from Switzerland and when he found out about Joyce miscarrying their child he married her. Unfortunately, this would be a mistake. Joyce was a materialistic woman who goaded Don into buying her expensive things. In the middle of all this, arrived one of Donald's wealthy clients, Ralph Mitchell. Restless with her life, Joyce had a one-night stand with Ralph. She decided to stay in town while Don went back to Switzerland on business. An observant Nancy took note. Soon after, Joyce discovered she was pregnant, again. The baby was Ralph's, but Ralph was not about to marry her, so Joyce reluctantly told Don they were expecting, and she vowed to get revenge on Ralph for turning her down.

Later, after losing this child, Joyce longed to see her son, Teddy, who knew he was adopted but had no idea that Joyce was his biological mother but Mary refused Joyce's request. Mary didn't trust Joyce, and for good reason. Then one day in May 1978, Don noticed that Mary wasn't looking well. Soon afterward, Mary was hospitalized at Memorial with hepatitis, and Teddy went to stay with Joyce and Don. When Mary recovered, the scheming Joyce said it would kill Don if the boy left. Since Joyce had lost "their" child, again. Teddy was the only person who could make Don smile. Mary adored Don and couldn't refuse him anything, so she reluctantly agreed that Teddy could stay for a while.

Afterwards, Mary was rescued from a fire by John Dixon, nemesis to the Hughes family. The recovering John was attracted to Mary, and when he asked to see her, the kind Mary could not refuse. As John's health improved, he claimed Mary was the reason. When John wanted a deeper relationship, with Mary, than the one they had, Mary admitted to John that she had been warned about him. John immediately suspected that it was Dan Stewart and concocted a plan to hurt his reputation at the hospital by spreading rumors. Soon afterward, Mary learned that John was telling everyone they were living together. That was the last straw, and Mary broke off all contact with John! For a while in the second half of 1978, Mary dated Bob Hughes but that ended when Bob became attracted to dancer Dana McFarland.

In January 1979, Don was still mourning the loss of what he thought was his and Joyce's second baby. Ralph couldn't bear to see his old friend suffer, and he told Joyce that Don must know the truth, that the baby was really Ralph's. Joyce was so desperate to stop Ralph that she planned to kill him, but her plan backfired when instead of shooting Ralph, she shot Don, paralyzing him. The police believed Joyce's story about a prowler, and she was cleared, but she worried that Ralph would figure out that she was really trying to kill him,. He did and confided in Mary, who thought he was absurd. However, when she saw Joyce freak out when little Teddy picked up a toy gun, she thought there might be something to Ralph's revelation. Mary investigated on her own and found out that Joyce had "accidentally" run over one of her ex-lovers a few years back. Meanwhile, Joyce had grown tired of being married to a cripple and had started to cheat on Don. As for Ralph and Mary, their mutual concern for Don brought them close together again, and Mary agreed to be his wife. Ralph confronted Joyce about trying to kill him so he wouldn't reveal that the baby's real father was Don, and Don heard the conversation over the intercom. When he confronted her, Joyce swore that she did it all for him, but Don wasn't buying it this time around. Joyce raced to her car and got pinned between the car and the garage door. Ralph saved her life, but Bob diagnosed traumatic shock. Don forgave Ralph for his affair with Joyce, and Ralph urged his friend to have her committed to a sanatorium. Joyce overheard their conversation and escaped, kidnapping Teddy. She merely wanted to say goodbye to Teddy, though, and returned him home to Mary. Shaken and upset, Joyce drove out of town. Her car plunged off a bridge, but her body was not found.

Mary might have been engaged to Ralph, but she still had feelings for Don. Don's paralysis had led to a deep depression, and Mary was determined to bring him around. One afternoon, while Don was showing Mary his physical therapy exercises, he experienced a sensation in his legs. Elated, Mary and Don shared a spontaneous kiss, and Mary bolted. They agreed to try to forget what happened, and Mary went so far as to tell him he better start looking for a new secretary, because after she married Ralph, she didn't intend to work. Mary delayed her wedding, but she remained adamant about marrying Ralph. When he recovered, a disappointed Don told Mary he was thinking of going back to California because he couldn't bear to see her with another man. Don's mother, Nancy, suspected that Don was in love with Mary, but Mary couldn't bring herself to tell Ralph that she no longer loved him. Even after she accepted his engagement ring, Ralph had reservations about the relationship because he sensed Mary's feeling for Don, and he couldn't let her marry him if she was in love with someone else. So, Ralph ultimately broke off their engagement. Soon after, Don got the court to declare Joyce legally dead, Don finally persuaded Mary to marry him and they got engaged, setting the wedding date for June 1980.

On February 14, 1980, a very much alive Joyce shocked everyone by returning from the dead at Donald and Mary's engagement party. At first Don, Mary, Nancy and Chris were certain that Joyce's being alive would hamper a wedding between Don and Mary. However, Joyce surprised everyone, again, by deciding to free her husband legally. She told Donald her only reason for living was Teddy, and she swore she'd never tell the boy she was his biological mother. Donald was skeptical. Joyce again surprised everyone, when she went to the police station and turned herself in for shooting Don. She admitted she had meant to kill Ralph Mitchell, and she wanted to pay for what she'd done. Don decided not to press charges. Grant told him it was extraordinary that Joyce stepped forward. This was the Joyce he knew and married in San Francisco. Joyce remembered how her father had walked out of the family, and her mother, blaming her for the desertion, put Joyce in a foster home. The only thing she had from her mother was a treasured glass unicorn. Joyce realized that she gave up Teddy because she grew up believing children destroyed marriages, and she feared Grant would leave her if he knew they had a son. Obsessed with Teddy, Joyce egged on Donald to convince Mary that she should let her see Teddy once in a while. Mary agreed to an occasional visit but soon realized Joyce was just as neurotic as ever and reversed her decision, leaving Joyce devastated. Mary even went so far as to ban Joyce from Teddy's birthday party, and she and Donald had a falling out over it. As Mary continued to turn Teddy against her, Joyce turned to Grant, asking him to set things straight. When Grant gave Mary a letter from Joyce to give to Teddy, Mary ripped it up, and the two women had a knock-down, drag-out fight that ended in Mary slapping Joyce. While Don and Mary's relationship was deteriorating over Joyce, Joyce and Grant were growing closer. Joyce told Grant she wanted to set up a trust fund for Teddy, which made Mary furious. She was sure Joyce was doing this to get Grant on her side.

Everything came to a head on November 5, 1980, Mary went to Joyce's apartment and Joyce told Mary that maybe Teddy would be better off if he knew Joyce was his biological mother! Upset, Mary told Joyce she planned to leave town with Teddy. As Mary rushed out of Joyce's apartment in a fury, she accidentally knocked over and broke Joyce's cherished glass unicorn, escalating Joyce's hysteria. Joyce ran after her, and in the confusion Mary fell of a balcony. When the police arrived, a neighbor told them she saw Joyce push Mary. Joyce was arrested for attempted murder, and if Mary died, the charge would be murder in the first degree! Even Grant had doubts about Joyce's story that it was all an accident. Joyce was sure, though that when Mary woke up from her coma, she'd tell them the truth. Nancy was taking care of Teddy, and she, too, was certain that Joyce had pushed Mary off the balcony. When Joyce was released on bail, she went to see Teddy, but the boy lashed out at her, saying she'd pushed his mother off the balcony and he hated her! Just before Thanksgiving, Mary regained consciousness and told the truth, exonerating Joyce. As far as her relationship with Donald was concerned, in Mary's mind it was over, and she planned to return to Laramie. Before she did, she gave Joyce permission to say goodbye to Teddy. Teddy said he knew his "aunt" Joyce didn't hurt his mom and he hoped she'd visit them soon. A tearful Joyce told her son she loved him very much.

Mary was like a second daughter to Nancy and Chris, and it was a sad goodbye. Donald tried to get her to change her mind, to no avail. Soon after she left, Mary was in a terrible car crash and was not expected to live. Teddy came back to Oakdale, for Christmas, and Nancy readied Donald's old room for him. Everyone feared what Joyce's reaction would be to Teddy's return. Nancy followed Mary's wishes and kept Joyce from seeing Teddy, but Joyce insisted that as Teddy's legal guardian, Grant should be making the decisions. When Teddy asked to play with Joyce, Grant gave the OK, and the boy began to visit with her more often. One night Lisa dropped by and was horrified to find Joyce and Grant alone together! Lisa was certain Joyce was trying to win Grant back, but Grant explained they were just friends and Teddy was the focus of their relationship. Joyce tried to get into Grant's good graces by faking a serious illness and it would have worked if Lisa hadn't caught on. Exhausted by the scheming women in his life (Joyce and Lisa), Grant decided to leave Oakdale. Around this time, Mary awoke from her second coma and Teddy was sent back to Laramie to live with her. Joyce, not seeing any reason to stay in town, also left. Later, Don also left to join Mary Ellison in Laramie, and the two were married.

Sometime between 1982 to April 1985, the Ellison farm, like many at that time, went under and Don and Mary and Teddy relocated to San Diego, California.

In April 1985, Don attended Bob Hughes's wedding to their longtime friend, Kim Sullivan Reynolds Dixon Stewart Andropolous. Mary did not attend the wedding, but Don told his nephew, Tom, and Lisa that he and Mary were still happily married and Mary was pregnant. In June 1986, both Don and Marry returned for the funeral of Don's father, Chris Hughes. At this point, Teddy was at a boarding school in Switzerland. Don and Mary showed off their new baby girl named for Chris and Nancy, Christina Nancy.

Don and Mary visited Oakdale again in 1993 to attend an anniversary party for Bob and Kim. That evening, Mary caught up with old friends, including a visiting Grant, to whom she showed pictures of Teddy.

In December 1995, Teddy, now going by the name of Ryder Hughes, decided to attend school in Oakdale. Don returned with Ryder and helped him get set up to live with Nancy and her new husband, Oakdale police Lt. Dan McClosky. Don and Ryder said that Mary and Christina Nancy were doing fine, although Ryder was slightly annoyed at times with his kid sister.