Depends what you want your accommodations to be like with the camper, and how big the kids are.
New to the game and wanting the luxury of a RV with the mobility of a pickup truck, you'll likely want a big TC that has room for all 5 people and big tank capacities etc.
Coming from tent camping and anything with a toilet and a roof is a luxury and a kid or 2 can sleep in a tent or on the floor? You might get by with a heavy half and a popup camper.
But in general, 1/2 tons and TC's don't mix well.
I'll leave the axle weights and all the gvw drama to the rest of the group here.
For us (family of 4, boys are 12 and 16 now) we came from tent camping and got a TC several years ago. Both boys, at the time 7 and 11, fit on the dinette bed. Current camper has a pull down bunk, so it still works, but have kicked them out into a tent the last couple years. Camper smells better that way! lol
That said, we have a short bed model with a full slide and for us it's the right size. We don't live in the camper unless it's pouring rain or something though. Generally hang out outside, cooking is 50/50 in or out.
If starting from scratch, I'd be ideally looking for a long bed 3/4 or 1 ton and a relatively large TC. Short bed truck if that's preferable to you for the rest of the year, but then 8.5-9' is the max size camper you can haul.
