I originally bought 2 chickens, straight run, but the gentler one sadly died. The more aggressive one is now on its own (i have a suspicion its a rooster) and I’m thinking of buying two more chickens to accompany it. I’m scared it will peck the new chickens to death though. The older chick is about 3-4 weeks old and I think the new ones are about a week old. What should I do?