How did you get rid of the milk before bed? Also cutting down on sugar advice

My son is three and goes to bed with a sippy cup of milk every night, which I know is not good at all and that’s why I’m trying to fix the problem. The issue is he absolutely hates water, I even tried drinking more water to try encouraging it I thought maybe if Mommy did it he would want to also, well I thought wrong!

I feel bad for sending him to bed without anything because I don’t want him getting thirsty but he is sooo stubborn he would rather thirst before he touches a drop of water. It’s ridiculous. I’m just trying to get rid of the Milk sippy cup before bed, I don’t want his teeth to get “milk rot” and I feel like I’ve tried everything but idk.

Any suggestions?

Also I’m trying to cut down on the sugar he gets throughout the day so if someone has suggestions on that it would be so helpful to me!