a grandmother sits on a couch pointing to her distinctive curly red hair while smiling at her daughter and granddaughter. The mother and young girl both have the exact same curly red hair texture and color as the grandmother. All three women touch their hair simultaneously, marveling at how identical their hair looks. Other family members nearby notice the striking resemblance and point with amazement. A father figure holds up an old family photo showing the same hair pattern in previous generations. how physical traits relating to genes or heredity are passed from parents to children across generations