Thanks once again Linda. I guess I will just have to live with what I have. I believe that in the 1841 census, generally only children under ten had their specific age recorded. Otherwise the age was recorded to the nearest factor of five below. Thus I wondered if the age of 20 could have been a typo, ie it should have been 40. Thus if their mother Christian had given her age as 44, that would have fit with her year of birth. It had just seemed strange to me that if their mother were still alive that she wasn’t enumerated with the 2 younger children. Anyway, case closed.