Hello! I’m new here! *waves*
I have 2 baby bunnies, one 5 weeks old (Buttercup) and one almost 10 weeks old (Willow). They are both female and both living in the same cage–for now. I know that I will need to separate them eventually, but I am not sure exactly when to do this? I will be getting them both spayed when they are old enough, and *hopefully* will be able to bond them to live together. If not, I have a back up plan and have plenty of space for both of them to live separately.
My question is: Willow, my 9.5 week old bunny, occasionally chases Buttercup, around the cage and up the ladder to the second level
At first I thought she didn’t want Buttercup upstairs, but she has since been totally fine with her being upstairs and doesn’t chase her. She chases her maybe once or twice a day and its very short lived- maybe once or twice around the cage. It usually happens when she has a ton of energy and wants to be let out to hop around. I haven’t noticed any other kind of aggression and they seem to get along great- sleep together, groom each other, eat together, etc.
Are they just playing? Or is this a sign that she is going through puberty and I should separate them?? 
Please help!
Thanks! 