Integrating small hens and roos into existing flock

[Crestcrazy2]

I am about to integrate my chicks that are about 12 and a half weeks old, these are the breeds.
1 black sex link 1 rir 2 silkie bantams and 1 ee roo .( I think both silkies are male also) I was wondering if I should be worried about my rooster?, I let the RIR out today by him and he winged danced around her and tried to mount her should I be worried if he tries to mate with them? , will it hurt them because they're small or will it be fine?, also should I keep the silkie bantams in something until they're full grown or should I let them out with the rest when I do integrate them ? Any help is appreciated and thanks in advance

 

[Pork Pie]

In my experience they should be ok. Check out this link - https://www.backyardchickens.com/threads/topic-of-the-week-adding-new-chickens-to-the-flock.1164542/