Jeff was born in June 1979. Jeff's parents divorced when he was three, and his father remarried and moved to Arizona.
He was a Captain in the United States Army Rangers. He was killed in February 2015 at age 35 in Afghanistan, during Operation Enduring Freedom, about 8 months before the start of the series. Natalie was pregnant at the time of his death, but it is unknown whether Jeff knew about the pregnancy.
During Withdrawal, Natalie loses her wedding ring and panics. She collapses after having a cardiac event and is diagnosed with a condition colloquially referred to as "broken-heart syndrome", brought on by extreme grief. During the same episode, at the suggestion of her mother-in-law Helen, she goes to his grave and leaves her wedding ring with him, accepting that it is time to move on.