Martha J Stewart (Motley) - Help

Consistency Check: More than 22 year age difference between Martha J Stewart (Motley) and her husband James W Stewart, Jr.

Is her birth date correct?
If so, she is quite a bit younger than her husband but also her mother per FAG is Martha who was born in 1736 Martha Motley
We KNOW she is the daughter of Patriot Capt Joseph Motley but not which wife-- maybe Elizabeth Motley ?
Lastly, we know per DAR she is wife of James Stewart

Please check the profiles and add sources if you can?
TIA