I don't think you can speed up the time it takes for your Tama to grow, but here is how quick they grow:
Egg >> Baby = One minute.
Baby >> Toddler = One hour.
Toddler >> Teen = 48 hours.
Teen >> Adult = 48 hours.
Adult >> Able to Marry = 48 hours.
At least, this is what I have come to conclued (Is that a word? From conclusion =P) If it isn't right then it's on the outskirts of being right ^.^