What to do.....??

[Milz]

Here's the situation. My cat, Harry, has been an indoor cat since his 
mother abandoned him on my back porch five months ago. Harry often 
sits on a favorite window sill and looks out. For about a week, Harry 
has been communicating with a group of alley cats. They sit directly 
below his favorite window and they stare each other for minutes on 
end. I thought it was healthly for Harry to interact with other cats, 
so I didn't try to stop him.

Friday evening I went outside to throw out the garbage. As soon as I 
opened the door, a black kitten no more than 2 months old barrelled 
into the house and hid under the sofa. I couldn't get the kit out, 
but Harry did. Harry wouldn't let me near the kitten to remove him 
from the house. So I capitulated and allowed the kitten to stay. I 
figured that Harry was a little lonely and bored and another feline 
might alleviate that. They got along famously over the weekend. Harry 
taught the kitten to use the litterbox and is sharing his place on 
the sofa and the window with him. Everytime I opened the kitchen or 
front door, the kitten would run and hide. Last night the kitten let 
me pick him up.

Here's the problem: this morning as I left for work, I opened the 
door and another kitten (light grey and white) barrelled into the 
house. I tried to get that one out too, but I was getting late for 
work. So I left it there. I don't mind taking care of three cats, 
especially since the weather's getting colder, and I plan on reading 
Harry the riot act when I get home. I have an awful feeling Harry has 
invited these kittens to stay and I have an even more awful feeling 
that this is just the beginning of a kitten migration.

Any suggestions? 

Milz