My friend recently got two ducklings but no longer wants them any more and wants me to take them off her hands because I have so many animals and she knows they'd have a good home. Buttttt I will be getting 10 ducklings possibly april 22-june 3rd (depending on when all the ducks we wanted are available) so if I took these ducklings from my friend and they got bigger and when my 10 other ducklings come and I mix the two is there going to be fighting? when could I mix the two age differences?