We have two girls and though they each mount one another from time to time, only one causes damage to the other. When Connie mounts Julie, Connie pulls hard on Julie's head feathers to the point that she's now pulling them out or breaking them. We've been dealing with our first case of bumblefoot (in Connie) so we hadn't noticed how thin the feathers had gotten till now. Connie has mounted Julie for a very long time, so I know she's not doing out of stress due to the bumble. Is there anything we can do to prevent Julie from losing more feathers?