It may be tough at 15 months, but if he is smart, he will pick it up. Just be CONSISTANT!
I recommend the book "Potty Training in Less Than a Day." The doll thing mentioned below was adapted from that.
Below is a reply to a post I gave to another mom:
I have boys. I also potty trained at a day care for years.
Get a doll that "goes" (urinates). I used a "water baby" Cabbage Patch Kid (has a drain hole in the crotch). When the doll is "full", put it on the potty. Your son will see it urinate in the potty.
Leave it there while you get your son ready to do his business. When he is not looking, drop a tootsie roll under the doll. Get excited that the doll has "pooped". Give the doll a sticker or put one on a chart (whatever works for your son). Then say, "your turn".
If he does not want to stay on the toilet for lack of something to entertain him, set up a TV tray with books, puzzles, games, etc. that can be wiped off easily and kept in a bin in the bathroom.
Hope this works. :o)
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