I am intrigued by the letter M noted on Vera's 1939 record. It seems to have been written in the same black ink when she married and her name changed to Harrison. When the record was amended to Foster with the area code and date it was in blue ink, the M has been crossed through in blue ink at that time.
Maybe it stood for "married" but why cross it out

. Just posting my observation in case anyone else can offer suggestions.