My parents dog does this with them too. He is a 13 year-old miniature poodle and "needs" to go out every morning at 4:30. My mother is exhausted and really would love for him to sleep through the night, but she allows him to dictate his "schedule". They have not set ground rules or "penned" him in their bedroom to prevent accidents through-out the house if they ignore him. (A dog will not have an accident in their sleeping space, unless they are confined for an inordinate period of time, or they have an infection or are sick.)
However, when my parents travel and we watch their dog at our house, he NEVER goes out at all during the night. Doesn't ask, nothing. He goes out in the morning with our two other dogs when we get up. He is an angel. He knows the rules and follows them.
Did this new routine start because of some event? Our dogs (Airedale Terriers) will sometimes get into this type of routine if we allow it.
When our oldest was sick with the stomach flu he needed to be fed 1/4 cup ground chicken pate every two hours. After he was better he wouldn't eat his regular food (completely ignored it!) and expected not only the pate, but also to be fed at the previous schedule. It took a few days of telling him no and only feeding him at the appointed times, he eventually got the picture and now behaves fine.
Also, taking them on daily walks have really helped with their energy levels. Dogs like yours and mine need time exercising with their owners on a daily basis to be happy and healthy.
Good luck with your wonderful dog! Your son will be happier and healthier growing up with a canine friend in the family.