Hi cheecky face
The marriage entry for your grandmother (1908 Derby) actually has her as Mary Elizabeth Waldram. Have you found her in the census prior to her marriage? For example, I think this might be her in 1891 (surname entered as Waldam):
RG12; Piece: 2727; Folio 110; Page 4
33 John Street, Derby
Elijah Waldam, Railway Cut(?) Porter, 38, b. Derby
Betsy Waldam, wife, 35, b. Derby
Mary E, 5, b. Derby
Arthur, 3, b. Derby
3 male boarders
1901
37 Yates Street, Derby
entered as Waldram
Elijah, 48, Railway Cut(?) Porter
Betsey 45
May, 15, domestic servant
Arthur, 13, errand boy
Ernest, 6, b. Derby
Elijah looks to have been the son of William & Ann Waldram
William born Osgathorpe, Leicestershire & Ann born Belton, Leicestershire
Just wondering how far you've got with researching the family back through the years? (don't want to send you info you already have)
Dazey