會好disturb 小朋友訓覺! I don't think you need to 每晚wake up 佢去wee wee!
In my daughter's case, I will have her wee wee before she goes to sleep every night. And that is good enough as she does "not" need to wee wee one more time in the middle of sleeping.
Every morning she wakes up, she goes to wee wee first thing in the morning.