Blimey, this is like a late night BBC2 play..!
David Childs died at birth 1866 and Matilda Haszel, witness at marriage one is Josephs sister.
Strangely enough Richard Haszel married an Alice Brown in 1883 and left their first child Alice born 1883 with her parents. They had three more kids but Alice remained with her parents. Alice herself married a young Italian builder in 1906 called Felix Geninazzi. Hard to picture the way they all lived then but not exactly prim and proper Victorian manners!
I also found a census for Joseph Hazell 1881 living in Luton as a lodger, born 1839, Ipswich and an engineer. Deborah ends up living in Luton too.