You missed a fourth possibility. Mary and Nancy were the same person. The Census has been known to show one person with two or more different names in different years. Elaine Oakes >>As for your original question of whose mother is who, I would say there are 3 obvious possibilities Mary died in 1850 or 1851 and Joel married Nancy who is mother of all children Mary died about 1853 possible due to childbirth of second child and William is her child and all the rests are Nancy's Mary died about 1857 and only Amanda belongs to Nancy Of course all of these are suppositions and may all be wrong. I was taught to look for second marriages even if the wife is the same name if there is a break of 3-5 years between children. The other possibility in children who did not survive to be listed on the census.