Babysitting cat who is scared of out of the room time

[Karen]

Yup, play and "successful hunting" will help bring him out of his shell, and patience! I agree, you want him to be more secure before he interacts with the others, so they don't think of him as prey - "if I attack it will run away, how fun!"

[krazyaboutkatz]

You might also want to try feeding or giving treats to all of the cats at the same time in the same room. If you've ever watched the series "My Cat From Hell", the cat behaviorist has had owners do this with cats that didn't get along and it's worked out well. Good luck.