Maybe Chrom's family have some sort of werid gene thing that deterimens if the brand surface.Since Lissa's brand never surfaced that likely makes the gene recessive with25% of appearing in each child. Chrom has6children so1.5children don't get the brand.But Chrom does not have the best luck stat so unlucky children.However Olivia gives her children luck+4 making Inigo lucky.GCSE biology is useful?