So I've got several white leghorns that are all the same physical size, but they may be as much as 2 weeks apart by birth. They were all born mid-April to beginning of May, so that would make them 20-22 weeks old roughly. I have 7 right now, but had 20. They all had small combs as they became "full sized". Now, I have one whose comb and wattles are markedly bigger than the others and one that's kind of in between. There are no other signs such as tail or saddle feathers, but I've never had leghorns before this year. I bought them all as pullets, of course. Here are a couple of pics. The one in the foreground has the larger accessories. The ones behind it are for reference with smaller comb/wattles. Roo? Or just proper development for a white leghorn at this age?