Sirius hadn't been expecting the kid to go charging at him, and before he had the time to step sideways and dodge, a fist connected to his chest and they were both tumbling back in the sand. Although he landed on his back first, Sirius reversed positions, rolling over and pinning Teddy down, hands gripping arms and legs solidly pushing the boy's legs into the ground so he couldn't kick his legs or try punching again. Sirius had him down good and was so bloody tempted to pummel the kid right there and then. His side ached bad, the berk deserved it, but something kept the knuckles from flying.
"Listen to me, you stupid little git," Sirius snarled. "If you knew anything about your parents– hell, if you knew anything about anyone, you'd know no one stays the same person. People change every year of their lives and from what I understand, circumstances weren't so great when they fell in love and made you. And if you think things are just going to go back to the way they were before, just because you want them to, you're a selfish prick."