I'm curious as to whether holding Roos from the time they are chicks might cause them to become aggressive to people as they get older? So, I'm doing an unofficial survey with your help ... I only want to hear from people who have/had Roosters that are/were five months old or older. Most Roos don't seem to turn aggressive until at least that old. The older the Roo the better. If your Roo is/was aggressive was he raised by people who held him a lot? If he isn't/wasn't aggressive was he held a lot? My girls held our chicks almost every day from the time they were a couple of days old. Our Roo became very aggressive when he was five months old. Hope this makes sense.