Lucius would have accepted a ravishing defence of his uncle, but obviously Nott treated his son like he had his sister, and Lucius couldn't tolerate that. "None of that, son," he said, rather coldly. "You want to play the diplomat, you do it with your house mates, but not with family."
He was angry, not at the child, but at Belinda for not taking care of the problem, for not telling him, but most important at Nott for whatever he'd done to this boy. "If he touches you anymore, you tell me. Do we understand each other? I will not have my child treated like a house elf. You are a Malfoy and everyone owes you respect, because you are better than they are, and that includes your uncle."
He rubbed his fingers, almost feeling a physical need to hex someone, before forcing himself to relax. "We'll find an arrangement before the Christmas holidays."