Those look like red sex-links, not rhode island reds; even hatchery RIR's are a much darker red; exhibition ones loost almost black they are so dark. Yes, breeds can cross, and if a frizzle rooster was in with them, then he could father some of the chicks.
that would be just too cool if its from the frizzle chicken. the thing is that they dont always com out frizzles but carry the geens.. would i be able to tell even if it doesnt frizzles? and thanks for the breed info i just have to remember ( red sex-links) they are good layers and 99% fertil eggs but none have ever became broony on me. now they stoped laying so maybe next year ill have the experiance of a broony hen.

Yea, we do love her. She's a pain in the butt, but she's my pain in the butt![]()
Its very possible your frizzle roo mated with those girls (and I agree, they look like red Sexlinks to me as well). If any of the chicks are frizzled, you'll be able to tell when their little wing feathers come in![]()