1901 census mystery

[dothawkes31]

Hi, there are two people we have never been able to spot on the 1901 census, they should be there, but ever since it's release and with dozens of attempts they will not reveal themselves! All their parents and siblings are there.
Edward Hale born 1 dec 1875 St George in the East son of a shoemaker married Matilda Killingback in 1906 at St Johns Limehouse.
BUT, in 1902,1904 and 1905 they had children together and on all 3 birth certs they have registered the children as though they were legally married .
Neither can be found on the 1901, the eldest child was born April 1902 in Poplar and so possibly they are together somewhere but we have tried all sorts of variations on the spelling of the surnames.
We have looked at a possible mis-transcribing from the original enmerators book by ancestry and FMP and still not uncovered them. It is possible I suppose that they were simply missed as they lived in the worst part of the East End for overcrowding.
Any new ideas would be helpful! We have all the baptisms and civil certs and their details from all earlier census returns, they both died in 1913 and we have them on the 1911 together.

[craft1948]

There's a Susan Groom born c1862 died in Kent in 1904.

[dothawkes31]

I've found a Susan Groom aged 80 and a Susan Groom aged 39 living together in Kent on the 1901, Mother and Daughter both were actually born in Norfolk