For what you're trying to do, I think the 35mm f1.8 would be a great fit. I recently did a miny photo session for my friends with their kids and used primarily the 35mm. They turned out great. The "rules" of photography say that you should use a longer focal length for the most flattering portraits but this lens will still do you very well. As WooD alluded to, as long as you don't need to get
really close, 35mm should be fine.
And it's great for low light.
