I am sure over time they will all be fine with each other. My RB Shadow used to bark and jump at the cats when he would get excited and want to play. He was trying to intice them into a game of chase. It usually worked. Especially with Vixen. He would flatten himself to the floor, stick up the butt, bark and then make a jump at her. She would proceed to swat him and then jump over him, attack his tail and then they were off. Always playing. He never once hurt her. She was only a little thing of just over 1 lb when they started that and he was 140 lbs.

Don't worry Jen I am sure they will all start to get along and once the kitties realize Roscoe wants to play and not hurt them then you will have regular races aroung the house.