Is this just my kid?
My 3.5 year old found the markers and started coloring on her own for 20 min. And I know what you’re thinking but every single marker that is not in her hand has the correct cap on and she has only colored the paper and only on her coloring tray. How? Simple she is an aggressive rule follower. The down side you may ask? She will not eat, sleep, go potty, play with her toys, or do most things without asking and hearing a clear “yes”. She has peed her pants because I was doing the dishes and did not hear her ask to use the potty(which she can use fully by herself). She will ask me if she can play in her room with her toys by herself. I never have to tell her no more than once. But also she will try to force rules where they do not apply(such as taking off shoes inside while at a restaurant or store). I would like to add that I didn’t do this. We have never made strict rules and are not authoritative parents. She does this to herself.
Maybe while the rest of us deal with training our wild children maybe you have the unique task of teaching her how to be silly and “color outside the lines.” Mine color on the walls and each other so I have no advice lol.