welcome Alicia! Amy is right about holding the camera and the Rebel. It will auto focus with the 50mm 1.8 which is a nice lens for toddler action and low light. (and fairly affordable!)
Wander around the other threads, there are a lot of ideas/opinions about Nikon or Canon. I'm a Canon girl but won't hold it against you either way
I'm not certain about Nikon's Live View LCD, maybe somebody can chime in about how useful it is.