I completely understand the dilemma. How are the rest of the adults in the ward? Are they people you'd want to share the tent with? Some of it also depends on your $$ status and how much you'll camp with SB and the kiddo. PAC just got
this at REI and really enjoyed it. It's a two-man tent for $100. If money weren't that much of a factor, I'd suggest a one-man
and and larger one. That way, you have options. If you don't plan on much family camping and the other potential leaders are the annoying types, I'd go with a one-man or a small two-man -- more than likely the other adult leaders will have multiple-person tents that you can use if they're cool people. If not, "Sorry, guys, it's made for one."
The ultra-minimalist/ultra-isolationist...
Considering the Texas weather, that should work, shouldn't it?
And only because the thread made me think of it, remember the first episode of Curb Your Enthusiasm? The pants tent -- that's one to avoid on the campouts!