If you have an open loft that is all the birds are not contained in their own nest boxes then the sire of the young bird can be any cock in the loft.Now if they are in their own nest box we need to see the parents in this way we can determine what the factors they might be carring. I suspect one of these birds is carring OPAL or is infact an opal. Recessive opal (o) proudces a variable effect from NEAR normal to intense colorations.Lacing,pastel pinks and delicate reds often are expressed in the wing shield.I believe that the red bird in this pair is a recessive OPAL,but I would like to see a picture of the red bird. With the wing open and the tail spread.GEORGE
The bird described above is most likely a recessive opal, as you say. Recessive opal is a simple autosomal recessive so both parents just have to carry the gene to make this occur. It is quite common in homers.
Dominant opal would be a possibility but these will usually show some signs in the plumage, still some are hard to recognize as dominant opals. In mine, I don't get clean white bars without other factors to help clean them up.
Toy stencil is another possibility but is less likely to produce a good white bar from two birds with normal coloration than is recessive opal.
This blue white bar will be a hen as it comes from a sex linked mating as we have discussed many times.