is Margaret the mother of John ?

[audrey]

just found another child for the Sewell below
Margaret Sewell b 28/2/1808 but  I can find no further reference to Margaret death or marriage  I am now wondering as I can , find Christ.for all those below except John Sewell age 15 years  a Pos . candidate for my G.G.grandfather could he be the son of the missing Margaret Sewell and not the son of John and Mary? and I have yet to find the Mary age 6 Mt's

1841 census
Botchergate, Carlisle
John Sewell  55  Cotton Weaver  Y
Mary  55  Y
William  30  Laborer  Y
Sarah  25  Y
Mary  25  Cotton Factory  Y
John  15  Cotton Factory  Y
Mary  6Mt's  Y
HO 107/175 05  Page
these Sewells are a nightmare

thanks

Audrey