Potty training is hard. In order for your son to become interested in doing it, you have to make it fun.
To do this you need a target to pee on. Whether he is sitting or standing, having a target and making sure to laugh loudly when he hits it, will make him want to use the potty, not reject it or fight it.
Start with some toilet tissue, and move onto other things to keep him interested, like colored squares of paper. We let our son pick his own color, then sit and pee on it. Potty time is now easy and fast.
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