again, 10 years old. at that age, especially when you live privileged as a noble's kid, his definition of consequence is probably skipping dessert. especially when he is convinced the MC is evil.
in his head, MC is a thief who went inside his house, and is attempting to kill his father. and he did tried to shoo her with the pranks, with the maids on his side, etc. but nothing's working. he's desperate.
RL example, i smashed by big brother's head with a cane when i was 8 years old. he's teasing me nonstop, and i got angry. didn't even realize i have a caane in my hand until i see blood gushing out of his forehead