C.S.
I know a lot of people are against the pull-ups but they worked really well for my son. Once he understood the idea of going in the potty it was just matter of him getting past his stubbornness and the pull-ups allowed him to take control of the situation. When he did decide he wanted to used the potty he could pull his own pull-up up and down and eventually he was keeping dry at night. It saved me from having to take his diaper on and off for him and saved me from cleaning a lot of messes. I really think it just depends on the kid and you might try it especially with them still being in the crib. I would be more concerned about them actually being ready when you wish them to be, it will be really hard to train them if they are not ready mentally as well as physically. Good luck and happy holidays!