Welcome to the forum, Joe!
2 adults and 3 kids... We're 2 and 2 in a 13'er and I'll hafta say, that's pretty much the limit, unless you can put some of them in the tow vehicle or a tent. If they're really small you might squeeze 1 adult and 2 small kids in the dinette bed (it's only about 45" wide in most 13'ers), or 2 small kids in the bottom bunk in opposite directions (it's 24" wide), but that won't last long.
If you want a trailer you can grow with, look for a
Scamp 16 layout 7.
Casita makes a similar model. Both will require a somewhat larger tow vehicle.
Scamp L7.JPG
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