Sisters are always drying their hair. Locked into rooms, alone, they pose at the mirror, shoulders bare, trying this way and that their hair, or fly importunate down the stair to answer the telephone.
Phyllis McGinley
For there is no friend like a sister, in calm or stormy weather, to cheer one on the tedious way, to fetch one if one goes astray, to lift one if one totters down, to strengthen whilst one stands.
Christina G. Rossetti
Sister is probably the most competitive relationship within the family, but once the sisters are grown, it becomes the strongest relationship.
Margaret Mead