Thank you so much for the information. I will now have to see if I can check out the official records. I know that I have found a Jane Kilner is Boston in 1860 living with her mother Elizabeth which is the right age. No Mary though. Quite possibly William and Mary might have died. My Elizabeth that was born in 1843 and immigrated to the US in 1850 named her first child Mary.
Thank you again for you assistance.