Potty Trained 2.5 Year Old Having Overnight Bedwetting Incidents

Pull ups overnight is fine. Children's bodies aren't always capable of controlling overnight dryness. Night time pants should be fine and since they're only for night time, no confusion issues during the day.

Night time dryness is a separate issue from potty training. It's physiological development, not 'training' for night time. It's very common for kids to achieve night dryness later (sometimes MUCH later) than being toilet trained.
Use a Pull-up to make your life easier. When he is dry for about 10 days in a row, his bladder is developed enough to "hold it" all night!

My son went through this when summer hit because he was playing so hard and sleeping hard. He was fine waking on his own all winter or sleeping through and staying dry. Now we make sure to cut off liquids early in the evening which has worked. If he does have some liquids later, I set my alarm and wake him around 1 to go to the bathroom. I got soooo tired of changing linens in the middle of the night! Mine wouldn't put a pull up back on because he said it's a diaper and baby's wear diapers ( I have an 8 month old). One suggestion I thought was great for bedwetting though...layer the sheets and matress pads so changing at night is easier, you just take the top layer off and you're good to go.

Kids bodies are not developmentally ready to hold their urine overnight until, I think, around the age of 5 or 6. I have several friends with 5/6 year olds and most of them still wear a pull-up at night. I know there are some younger kids that can hold it all night, but that is not the norm. My daughter is 3 1/2 and there is no way that she would be able to hold it all night long. Even though we cut off liquids, she still wakes up in the morning with a wet pull-up. There have been nights that she has not peed, but I won't even try it until she goes 2 weeks at least without peeing. I wouldn't hesitate to put your son into a pull-up at night, it won't set him back. You don't want him to feel like he's not doing something right when he wakes up in a wet bed, so just set him up for success and let his body take its time. Hang in there!! I hate potty training! I have a 21 month old L. boy that I am not looking forward to training!!

Day training is about knowing when you have to go, and getting to the bathroom. Night "training" is not related and is not training at all. It's about the bladder growing and maturing to a point where it no longer needs to be emptied at night. There's nothing wrong with a 2 1/2 year old still needing a diaper at night. If you're afraid that he'll get lazy about getting up to pee in the morning, cloth diaper him at night. He'll prefer to get up and use the toilet than have to wait in a sopping wet cloth diaper for you to wake up, if he's having any on-purposes.

He may be constipated. The weight of the feces pushes on the bladder during the night and they have no room. Otherwise check him for UTI. If his urine is darkish or smelly he is dehydrated and needs more fluids, being dehydrated and having strong urine is hard on the bladder and makes it harder to hold.

I think a Pull Up for an almost 3 year old is fine.

But, if you don't want to go that route, go to Target (or Babies R Us) and get a Soaker Mattress Pad. It goes over the sheet and is easy to wash of your kid should wet it.

My cousin cuts off liquids early for her daughter, I think at 4 or 5 for her. I would use a pull up, I assume he knows how to take it off if he does wake up at night, or put a waterproof crib pad under him so he doesn't have to wear a pull up but the bed won't get wet. It is a body maturity that isn't really trainable so it will probably be hit and miss for a while.