Potty training

Potty training Aelita is proving to be far more difficult then i thought it would be. She will sit on her little potty for about 20 mins and not do anything and as soon as she gets off the potty she decides to go all over the floor. She likes wearing her big girl underwear though. I'm just really hoping that she gets potty trained before Kiana is born, but i don't see Aelita getting potty trained in 2 weeks or less.