A.C.
My daughter was fully potty trained by the age of 2 yrs. She too was tiny, still is at 9yrs old still wears 5's and 6's. Just keep going like you are and add the "big girl panties" and let time do it's thing. You may have to clean up a few messes, but it is so worth it in the end. As far as buying panties to fit, I just kept buying them until I found some that fit and held on to the ones that didn't for when she grew into them. Most brands are pckaged in resealable packaging now, so that makes it easier. Look for 2T bikini, they have a much smaller bottom in them. Another option is to find someone, if you don't have a sewing machine and take the sides up, we have had to do that with most of my daughter's clothing anyway. Just be patient and use pull ups for nap and bedtime until she has no more sleep time accidents. Best wishes to you both.