Sources

1 : ; Secondary evidence
Catherines birth year is 1855 so assume marriage before this?

2 : ; Primary evidence
1881 census for Netherfield, Sussex has age as 60 and occupation Housekeeper

3 : ; Primary evidence
Housekeeping for her son in law, William Collins, in the 1881 census for Netherfield, Sussex

4 : ; Primary evidence
In the 1881 census for Netherfield Sussex, Elizabeth Besesvetherick (60 - Housekeeper) was living with her SON IN LAW William Collins who was married to Katherine Thomas. Assuming her father died and mother remarried.

5 : ; Secondary evidence
After Katherines birth in 1855

6 : ; Primary evidence
Wife is a widow in 1881 census