You left out a few details like how big your family is? the age of your kids, etc?
I camped out of a big Coleman that was 13 x 9 for a few years and my two kids and I had plenty of room. Still have it but I wanted something a little more weather worthy and went with an REI Base camp 6. It fits the 3 of us (two kids 15 and 12 and me) with cots fairly well. It would be tight with one more but I like a lot of room. It's a 6 person tent and would be fine with one more but like I said I like my space.
This tent is awesome in the weather. The first time I used it we had thunder storms with significant wind for the first 3 nights. I never worried about the tent and we stayed dry as a bone, but was definitely worried about a tree coming down on us. There was some serious wind. The tent never missed a beat.
I read a review about how someone was camped on the beach during a hurricane and ended up abandoning the tent. They came back after the hurricane and the tent was fine. Anyway it looks like the price went up a little but I got it on sale and it's well worth the money. And easy to setup and stow away fairly quickly once you get the hang of it. Good luck with your search.