Originally posted by catnapper
Congrats! I'm sure the transition to 3 cats will be just fine. To make the move easier on all parties involved, put him in a spare room (even if its just the bathroom) for a few days before the girls meet him whisker to whisker. They all need to get used to the smells of the other cats, so give each cat a blanket or towel with the other cat's smell on it.
That's what I do when introducing a new cat into the house too. I keep the new addition in the bathroom and my other cats like to sniff and play footsy with the new cat under the door.