2 and 2: Hens and Roos

I have three chickens that were raised together: two bantam cochins (one is a boy) and a silkie. I also have a silkie rooster who I wanted to put with the silkie hen. I also have two houses with small attached runs inside a bigger run. Right now the three are in one house and the rooster is in the other. They have been in the big run all together, and pretty much stay away from each other. However, I don't want something to happen while I am not there. The silkie roo is pretty aggressive, but the cochin roo is laid back. Should I go ahead and put the silkie in with the rooster and just rotate who gets to go out in the big run? Or should it be ok if they all go in together? I am kind of confused. I have heard that you cant have two roosters together, but I don't know if this is true.