They don't see the 20-year-old with the mental age of a 10-year-old.

Here, a 13-year-old with the mental age of 6 will be forced to bear a child.

Keith, who is 20, has a mental age of about 5.

The boy had a mental age of about six, and that would never change.

The boy was now six, but he had a mental age of about two.

"I wonder what mental age they gave him* in the war."

Her mental age is not eight, it's older than sin itself.

He estimates her mental age at around nine months to a year old.

Our handicapped 18-year-old son has a mental age of about 3.

A medical report estimated she had a mental age of seven years and nine months.