Hi
I looked at this some time ago and thought that Robinson was such a common name and when it is Mary Robinson....
Anyway, as no-one has responded here is my two pennerth!
Kendal records should be on the IGI so the first port of call is
www.familysearch.org If that fails then it is more likely that she was born in an outlying village so you need to check them too.
Can you quote a census record? How do you know her age and birth place? Who and where did she marry? What did she call her children?
Maybe you have found her by now but if not then this may help.
Andrea