when would be a good time? I dont want to right now, but say around June or so when the weather warms up my nephews who live right next door accidently leave the door open and if I happen to miss it once...

I dont want my kitties getting lost or hurt... and we have a nice size backyard... Not fenced in yet.... Id like to make a cat run or something...

But if they got out... or *really* wanted to go out....

Suggestions?