I also didn't think Sebrights went broody. She's too small to mate with our roo, so ours will never have fertile eggs. I now have a funny image in my head of my 20oz Sebright trying to cover one of our Jumb oeggs. We have a hen that lays giant 4oz eggs. (Looks like a duck egg.)
Well if she tries to cover one of those eggs, I want pics!