Thanks all for the replies.

I suppose I was hoping for too much that Annie Maria had named her father on the marriage certificate Jennifer c but you never know. As she married under the surname Wood I assume her birth father acknowledges that he was the father, especially as she was registered under his surname and I don't believe Mary Ann married him.
Thanks Willsy, I'm surprised that Mary Ann may have claimed Wigston as her birthplace. That year is definitely their year of marriage. Thanks for also confirming it Carol18353.
Annie65115, Banbury is somewhere I haven't found mention of yet but I'm hoping that once I obtain the marriage certificate for Mary Ann's marriage to my grandfather it will help me to trace her.
That is most definitely the grave. No idea that Granddad had died in the mental hospital, I do know that the pain he was in drove him to distraction sometimes though. Irene Rose Morley is my baby cousin. Doris was known affectionately and Auntie Doll and for many years I believed she had only one child, my cousin Terry. Eventually mum mentioned that she had given birth to a daughter who lived for only three days. Mum said that everyone, even the midwife, said that Irene was too beautiful a baby to live for long in this awful world. I expect they were trying to comfort my distraught Auntie.
Uncle Horace was a stranger to all of us. He was a milkman for all the time I knew him but rarely had anything to do with family, preferring to spend his time balancing his milk round books and popping down the local for a pint. (He wasn't a drunkard as far as I know, just withdrawn but I do know that by the early 1970s my Auntie was unhappy in her marriage, to the point of wanting to leave her husband.
I believe Thomas' mother, Martha Frearson (possibly Bates) was also buried in this grave, as was my beloved Auntie Ivy in, I think, 1969. So was my equally beloved Grandma, Annie Elizabeth in 1975 less than a year after my darling Mum was buried in a grave on the opposite side of the green to so many of her family.