this is why socialization of your day old chicks is IMPERATIVE
you're more likely to get an aggro rooster when you have to many chicks to spend individual time bonding with them.
i have 10 right now and socializing them all using my very loving 3 year old. Our suspected cockerels are VERY friendly right now at 2 weeks old.
when i was a teenager i had a few roosters who were SUPER mean. One comes to mind who was the worst. Alex. everytime we got near him he'd attack, so we eventually started working on countermeasures. Swatting him never worked, kicking back worked sometimes, but he was a MASSIVE, jersey Giant, attacking back only seemed to fuel him
we tied his leg to a chain and gave him a 20 foot yard. that worked like a charm to keep the ladies in the run, keep him back from us, and the littles, and keep them all safe as he had injured and even killed off his own sons before.
one day he got off somehow, and i was coming home from school, as i got off the bus i heard a young child screaming for help When i came around the bus, our rooster was chasing a 7 year old boy home biting and drawing blood the whole way
We dispatched Sir Alex the next day.