hatching Black Copper Marans and BCM crosses

[Sherris Backyard Beauties]

My BCM's are hatching! Problem is My BCM crosses I dont know if it is from my Rhode Island White or my Buff Brahma Hens. Eggs looked almost identical. Some of them looked like pure BCM's and some look white with polka dots. I want more polka dots any ideas which hen layed them?

 

[DemeterAD9]

White with spots are likely from the RIW hens. If the RIW are dominant white, then crossing dominant white with black typically results in white chicks that can have black spots.

I've hatched a handful of white spotted chicks that came from a white American bresse hen and a couple that came from a Cornish cross pullet. Some of them ended up being pure white but a few stayed nice and spotted. This is the prettiest of the bunch though this isn't the best photo of her. Note the blue legs, she got them from her bresse mom.