How much should I worry that my 4 year old is struggling with potty training?

Generally speaking, I wouldn't worry too much, they just might not be ready yet. Every child learns at their own pace, and when they are ready, they will get it. By the time they start kindergarten, they can walk, talk, and are potty trained. Every child goes at their own pace, and that's OK. If they seem hesitant or afraid of using the potty, maybe try to find out what they are afraid of. If they seem completely oblivious and unable to have any sort of bowel or bladder control, that may be time to speak with their pediatrician about it.

Try not to worry. Remind yourself that sooner or later, your child will want to be dry for their own sake. If they start to see potty training as a battle with you, it'll be much harder. Leave the potty training for a month or so, then try again, slowly and calmly. A reward chart with stickers may help your child stay motivated. Making potty training interesting for your child will encourage them to sit still on the potty. You could keep certain books or toys in the bathroom especially for potty times. There's no need to keep your child on the potty for more than a couple of minutes. Praise your child when they manage to sit on the potty, whether or not they pee or poo each time. for other toddler issue you may go through; www.babyhealthcaree.com