What is Wee?
Wee is (adj) (in Scotland.) very small He’s only a wee bairn. I’ve had a big meal so I’ll just have a wee piece of cake. Antonym big a wee bit a little He was just a wee bit annoyed by my letter. in the wee small hours very early in the morning (noun) urine (child’s word.) The cat did a wee on the lawn. (verb) to urinate (child’s word.) Do you want to wee, Tommy? (NOTE: also wee-wee)
source: Easier English, Student Dictionary Upper Intermediate Level