Patrick the starfish has a pink body color which is dominant his wife for Trisha has a yellow body which is recessive they have 8 children. 4of their children are pinky while 4 of them are yellow. How is this possible?

Patrick is a heterozygous dominant (he have one allele for pink body color and one allele for yellow body color

His wife Trisha is homozygous recessive (she have two alleles for yellow body color)

When they mate their is a 50% chance that the offspring will has the dominant allele from his father and a 50% chance that the offspring will has the recessive allele from his father and his phenotype will be his father allele in both cases