Hi, T....
You should be able to cut back on the amount of liquid your son is drinking throughout the day...I would say let him have his milk in the morning when he gets up, and the last cup with his supper (so he can brush his teeth before he goes to bed, and not let the milk "sit" on his teeth all night). We have taken our son OFF milk (with his pediatrician's knowledge and approval, due to an ongoing behavioral issue). He gets ONE sippy cup with 1/2 water and 1/2 100% juice (we like Juicy Juice best, but any will do that does not have added sugar) in the morning with his dry cereal, and then one more sometime later in the day. The rest of the time he simply gets WATER, usually 3-4 total, but some days more, like really hot days. Doing the math, it seems your son is drinking about twice what our son is (Noah is 30 months old). I won't say that you are giving him too much, but I would ask if your son ever seems "lethargic" and "out of it" to you, and is his appetite good? If he doesn't seem to want to eat very much but still seems to have plenty of energy, I would say it's because his stomach is too full of liquid to hold solid food. If all he wants to do is drink, however, and his energy level is LOW, you definitely need to get him in to his pedi ASAP.
(I've been a Type 1 diabetic since I was 13, and I just turned 42. High blood sugars always zap my energy, and I get thirstier than normal on those days, as well.) Your pedi will be able to do a "simple" blood test (SOOO much easier than 29 years ago!!! YIPPEEEEE!!!!!) to see if his blood sugars are elevated. If that's the case, CALL me, and I'll be happy to help you with him!!
SO very glad your husband did not pass out with the news of the new baby!! (So much for "our" plans, right?? LOL)
Call me anytime, and we can talk! (going out of town on Friday this week, and will be back on Sunday night)
~J.~
###-###-####
____@____.com