Marc Brooks was the husband of Ensign Janet Brooks and lived with her aboard the USS Enterprise-D. He was born in 2329. Five months prior to stardate 44356.9, Marc died in an accident. The grief over his death led Janet to seek counseling from Deanna Troi.
Shortly following the funeral, Janet had all of Marc's belongings removed from their quarters. Unbeknownst to her, Deanna had saved one special item, a music box, just in case Janet changed her mind. Deanna returned the music box to her during a counseling session sometime later. (TNG: "The Loss")