Question: How is it that traits can vary so much in the same family?

One component, called shared environment, includes all environmental influences that make children in a family similar to one another.

Explanation: Environmental variance not due to shared environment is called nonshared environment; this portion of environmental variance makes family members different from one another.

stress fractures occur largely in the feet and legs and are common in sports that require repetitive impact, primarily running/jumping sports such as gymnastics or track and field.