You are just going to have to start potty training... plain and simple. My son was also delayed in his speech (same as yours) and I started prepping for potty training right before he turned 3 and then I had to bite the bullet and do it. I used pull ups and we just went into the bathroom every half hour and try. The pull ups have an area that shows you and the child if they are wet or not so every time you see she is dry, you give big praises. She is at an age now where she can understand when you tell her that it's time to get into big girl underwear because diapers don't fit anymore. That's what I had to do. And no, the pull ups don't hold as much as diapers because they are for training. So once they are wet, you need to put a clean one on. There are also Goodnights which are, for all intent and purposes, a nighttime diaper for bigger kids who wet the bed at night. They come in big sizes so you could even do those if Pull Ups are too small. Don't let the speech thing hold you back. I was scared to do potty training, but read up on how best to approach it. If you are consistent, it will work. Also, if you plan on putting her in preschool, she needs to be trained.