The one on the right is Karly, age 13, holding her sister. Guess her sister's age:
Continue reading for the answer…
From ABCnews:
Brooke Greenberg is the size of an infant, with the mental capacity of a toddler.
She turned 16 in January.
She never has been diagnosed with a genetic or chromosomatic disorder to explain the fact that she doesn't appear to age.
She still has her baby teeth.