While serving in Viet Nam, Jack Abbott met and fell in love with a young Vietnamese woman he knew only as Mai Yun. When Jack's military service ended he returned to her village, but could not find her, and not knowing her real name, it was impossible. Unknown to Jack, Mai Yun was pregnant with his son and had moved to a safer place. She later married a Vietnamese man with the last name Volien, and they had a daughter they named Mai. When the war ended the women were separated from the men. She later found out her husband had died, but her son remained missing.

In 1994, Christine Blair became friends with the owner of her favorite restaurant The Saigon Shack, run by a Vietnamese woman named Luan. When Luan was shot in a robbery at the restaurant, she pleaded with Christine to find her son, Keemo, before she died. Christine and Paul Williams traveled to Viet Nam, where they found handsome 20 year old Keemo who was belligerent and resentful, assuming his mother had abandoned him in Viet Nam as a child. But they convinced Keemo to return with them to Genoa City. After a tearful reunion, Luan recovered from her wounds. Keemo moved in with Luan and her teenaged daughter Mai. From stories Luan told her, Christine deduced that Jack had been Luan's lover while he was a soldier in Viet Nam and had fathered Keemo. Jack and Luan were reunited. Luan told Keemo that Jack was his father, which angered Keemo because he had always believed that his American father had deserted them. When Keemo learned how Jack and Luan had been separated, he accepted Jack as his father. Jack and Luan married, and they became a very close family, including Luan's teenage daughter, Mai.

Luan brought out a softer side seldom seen in Jack. They were married in a beautiful wedding. The bride wore Vietnamese traditional red, and Keemo as best man wore white. Luan had been ill, but she did not tell Jack. Ironically, Jack inadvertently discovered that Luan had a terminal illness. He resolved to keep his knowledge a secret so that her remaining months with him would be happy.

Jack got Keemo a job at Jabot working with Ashley at Jabot as a chemist. Keemo fell for Christine, but she was only interested in Paul. So Keemo became romantically involved with Mari Jo Mason. But he quickly tired of Mari Jo's mind-games and broke off with her.

Jack was devastated when Luan died. When Keemo learned that Jack had known that Luan was seriously ill, he accused his father of stealing precious time that he and his sister Mai could have spent with their mother. Eventually, Keemo forgave his father. To Jack's disappointment, Keemo announced that he was returning to Viet Nam.

Jack has only mentioned Keemo a few times in passing since, regretful that he is no longer in his life, and saying that they are still in touch. But in 2022 Jack began receiving texts wanting him to meet an address in Los Angeles. Phyllis tracked the address to a Hao Nguyen which happened to be the name of Keemo's mother's dead father. Asked if it might be Keemo, Jack admitted that Keemo had told him to stay out of his life shortly after he left in 1994, and Jack had no contact with him since. Jack did an Internet search revealing that Hao Nguyen, born the same year as Keemo had died 3 weeks earlier in Los Angeles – about the time the texts had begun. Finding the obituary, Jack identified the photo as Keemo. It said he had no survivors and had owned several properties in Los Angeles.

Phyllis talked Jack into going to the address in L.A. They found the house had been left unlocked for them. All that was left was a cardboard box. Inside Jack found a bundle of letters written by Keemo to Jack over the past year, but never mailed. Each was signed Keemo Abbott. Keemo wrote how he had worked out his anger and had forgiven Jack but was unable to tell him in person for fear the anger would return. Jack became very upset and wanted to leave. Phyllis found a photo in the box of Keemo with two women and a young girl in Vietnam dated 2012. Jack identified one of the women as Keemo's half-sister Mai. Inside a small wooden box was a wedding photo of Jack and Luan, and a necklace Jack had given her. Another photo, left there the next day, turned out to be of Keemo's daughter Allie. Keemo had told Allie that he never knew who his father was, just an American soldier in Viet Nam, so Jack was a surprise to her. The anonymous texter made sure that the two met. Although things started out very tentatively on both their parts, they hit it off, and after a few meetings she even hugged Jack goodbye. Allie was very bright, attending grad school, majoring in chemical engineering, a chemist like her father.