Hi S.,
I know that our culture really makes parents believe that we should be "training" our little ones to use the potty by 2 years, but unless you have to train him this early for day care, I highly recommend that you don't.
The majority of toddlers will start using the potty around 2.5-3 years old and it isn't unusual for boys to start much later - around 3, 3.5.
The earlier you start potty training, the worse the process can be for both mom and child unless the child has basically self-trained.
The best thing to do is to have the potty available and invite him to sit on it with his clothes or without. If your child starts having negative experiences with the potty and with the constipation already starting...these are not good signs that he is ready.
I know parents who have driven themselves crazy over the potty training experience for no reason. Your child is ready when he's ready and not before. If you're getting upset and frustrated with him over the potty, you're really putting a lot of stress on your relationship over something that doesn't need to happen until he's ready.
I'm sure you have relatives and friends who tell you that he "should" be potty trained by now, but please, put the psychological and physical development of your little boy first and tell them that he will use the potty when he's ready.
Put the diapers back on and put the potty chair away for awhile and enjoy your little toddler. Make this fleeting stage a good one without the stress. Parents want to control the 3 things in their children's lives that they simply cannot - sleep, food, and potty! Let it go.
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