Jeffrey MacDonald met Colette Stevenson when they were in the seventh grade. As reported by People, the couple had an off-again and on-again relationship throughout high school. However, the relationship became more serious while they were attending college. 

MacDonald said he proposed to Stevenson during their sophomore year of college, after she became pregnant. When discussing their decision to marry, MacDonald said he and his wife were "deeply in love."

During the early years of the marriage, MacDonald enlisted in the Army and was subsequently away from home during training exercises and deployments. However, the family was reunited in August 1969 when he was stationed in Fort Bragg, North Carolina.

By late 1969, Jeffrey MacDonald was a Green Beret and an Army surgeon. As reported by People, Colette was taking night classes to further her education. However, the family had a reasonably "normal schedule," and Jeffrey was able to be home on nights and weekends. MacDonald said he and Colette "were increasingly happy," as they had "never been so good financially."

Friends and family seemed to echo Jeffrey MacDonald's description of his relationship with his wife and children.

In an interview with People, family friends Rick and Judy Thoesen said Jeffrey and Colette MacDonald seemed to have a "very loving" relationship, and Jeffrey "loved his girls." Jeffrey MacDonald's niece Samantha said her uncle was "a really kind, generous, thoughtful man."