Conversation so far:
who is Julia Holcomb in relation to Steven Tyler?
Tyler persuaded the parents of 16-year-old groupie Julia Holcomb to sign over guardianship to him so that she could live with him in Boston.
what was Julia Holcomb's relationship to Steven Tyler?
In 1975, Tyler persuaded the parents of 16-year-old groupie Julia Holcomb to sign over guardianship to him. They dated for three years.

Question: when did they date?
Self-contained rewrite: when did Julia Holcomb and Steven Tyler date?