L.V.
I also have twins who are now 5. My daughter stopped wearing pull ups at night early in their 4th year. My son still wears them. On a very few occasions he has woken during the night and I have prompted him to go potty and a few times he has woken with a dry pull up but most nights he sleeps through the night and has a wet pull up. As you already know having twins yourself, they develop at different rates, and kids in general hit milestones at different times. It's totally normal for a 3 year old to still need pull ups at night. Don't stress over it. They will get there.