A blue-eyed boy and a brown-eyed girl were born in a family from brown-eyed parents to determine

A blue-eyed boy and a brown-eyed girl were born in a family from brown-eyed parents to determine the genotypes of the whole family.

Brown eye color is dominant and blue eye color is recessive. If parents have brown eyes, they may have children with blue or brown eyes. Therefore, in order for a blue-eyed child to be born in a family, parents must have genes for both traits and be heterozygotes.

So, A – brown eyes, and – blue eyes. The child’s parents have the Aa genotype, the blue-eyed boy has the aa genotype, the brown-eyed girl may be homozygous AA or heterozygous for this trait – Aa.