Having had experience with both, my first two had dummies, which we were able to take off them when they were 6 months and 12 months respectively. Paige on the other hand has sucked her thumb from birth and refused to take a dummy. She only sucks it when she is tired and touch wood it has not misaligned her teeth, but yes there is the problem of trying to get a thumb sucking child to stop. We are happy to let her suck her thumg for comfort, and really don't know when we will try to discourage her from doing it or if we will let her decide.

I have heard of people putting the nail biters polish on their kids thumb nails to stop them, but I'm not sure I'd like to do that to her. We'll just see how it goes.