I have a few chickens appearing in my flock with topknots. I did not know what it was until till little gal hatched and grew up. Both of these young ones have evidence of the polish gene. It just started appearing so it must have been hidden genetics from on of my first roos. I remember when I got him I not only thought he was a she but I thought he had a growth on his head. It turned out to that just just feathers were sticking up. I think he was the contributor of the polish genetics. Here they both are again a little older. The one on the top just sort of has a stand up hairdo but Sister, the on on the bottom has a full headdress. I have to trim it so she can see.