Hi Lisa,
I asked whether your mother (not grandmother) considered the Carringtons to be her grandparents when she was growing up - whether they were still part of the family after Marjorie married. This would be a good test to see whether the Carringtons accepted her as a full member of their family, and vice versa (i.e. adopted, rather than just called this in the census, like Mary's example).
I thought Marjorie was your grandmother, not your mother - sorry if I've muddled them up.
Sue