Well, I love my yorkie! He is sweet and playful and such a little doll. I have never had a maltese, but have a friend who has one. She seems to be very calm with several bursts of energy throughout the day. My friend also has a 7year old with a learning disability and a four year old. She has never had any problems with her dog and her children. I have a four year old daughter and am planning on having another child within the next year. This dog is definately mine. I didn't buy it for my child or future children, although I let my four year have supervised play with him.
I think to have a small breed with children is alot more work than a large breed would be, but this is the breed I want and I think it is worth it. And like others on here have said, when I need my dog to have a safe place when I can't be supervising, I put him in his crate or xpen. One more thing, If you are planning on having children eventually, I would expose your puppy to as many children as possible so that he/she will be used to children when you do have them. Good Luck!