It's wrong not to protect one's sibling from harm.
Alice and her sister Kate are at an intersection about to cross when Alice sees a car start through the crosswalk toward Kate.
Alice wants to start walking across the road.
Alice holds Kate back until the car is through the crosswalk.
Alice assumes the car will stop and starts walking behind Kate, but the car hits Kate.
Alice and Kate safely finish crossing the intersection and continue on their way.
Kate is severely injured and has life-long problems walking.