On her marriage certificate July 1888age is Full
Father William, dead
On the 1901 census (April),Maria gives her age as 35, birthplace England.
On her death certificate, Feb 1939her age is given as 70, provided by her son William. The original certificate was amended. It had given her age as 76
If I go by the census information, her birth year is 1865/1866.
If I go by the amended death certificate, her birth year is 1868/1869.
I realize we can't always rely on stated ages(
). I don't really have any more information re Maria.
Any help to break this brickwall is greatly appreciated! 
Thank you,
kptz