Yes I did see it on ancestry
I would suggest getting Ben Russell's death certificate in Bideford to at least rule that one out you didn;t say what year that was?
I am presuming before 1851 when Charlotte is saying widowed?
Are you also postive that Mary died ?
I know she isn;t with mother in 1851 but at the age of 13 she could be in
service herself although I did look in 1851 No Mary Russell of that BD in Devon
As for Marys birth according to 1841 neither her or father Ben were born in county so Devon is out...
Although Charlotte was born in Devon according to census
So it would mean if they married it was elsewhere and Mary was born somewhere else too as she was born 1839 you would need to look for possible marriage about that time or maybe 1837/8
I have tried FindMyPast site nothing comes up even with just surnames anywhere that matches them
I don;t think the marriage in 1841 is your Charlotte because she is with Ben Russell in 1841 & 1851 with son B Russell
What puzzles me also is that Charlotte Russell is not in 1861 Census in Devon so did she remarry ?
Its possible if Mary died that she could be also known as Elizabeth
I found a Elizabeth Russell death Barnstaple Devon 1844 Oct/Nov/Dec 10 33
Barnstaple was where Charlotte & Benjamin were in 1841