Chicken size

[LCchickens71]

Hi! So I bought 2 zombie chicks back in August with 2 cream Legbar chicks. Unfortunately one of the zombies did not make it. So the one I have is on the small side feathered feet 5 toes and clearly part silkie. I have been slowly intergrating them with the flock for the past week. Yesterday I put the 3 in the run with the big girls and of course the little one was picked on. She stayed close to the Legbars. I was wondering if I need to rehome her or just give it some time. She’s only 4 months old.