‘Mattie’ was her nickname. Born Martha Elizabeth STEPHENS to parents Levi and Rachel on the 11 Oct 1871.
She married Joseph Martin DENTON on the 1 Oct 1889 in Chattanooga Tennessee.
The place of her birth has not been firmly identified so if anyone has a source please share.
The picture below is a favorite because she is holding a doll in her lap. Note the hair bows.

From left to right: Effie DENTON, Ernest DENTON, ‘Mattie’ Elizabeth DENTON, Gladys DENTON, Myrtle DENTON
Here is a picture of Mattie several years later:

Martha ‘Mattie’ STEPHENS DENTON