His Father's Son Dr. Quinn, Medicine Woman : Season 5 Episode 24

Sully and Brian forge a true father-son bond when Brian's free-wheeling, irresponsible adolescent behavior puts him in mortal danger, and Sully disciplines him. As Brian's stepfather, Sully has let Michaela set the rules for Brian up to now. But when Brian's misbehavior with his friend Anthony puts them, and the town, in danger, Michaela and Sully realize that Brian needs -- and wants - Sully to act as Brian's real father and give the boy the boundaries he needs, which enhances and strengthens their bond.