Emma Wreath 1819 -
Wife of Christopher Petterson, thus Kitty's grandfather's wife. The 1891 Census below shows her as widowed (Christopher died, aged 60, 12 years earlier).
She is living at number 2, Lower Park Road, with two other families.
Daughter Katherine appears to work in the bookbinding industry and son William is in insurance clerk.
Emma's othe five children are not mentioned.