Hello Vicky
Have you looked at any wills, not just for Whiteheads but for families they married into? Sometimes you can find an incredible amount of info that will help cement - or upset! - a family tree, like married names of dtrs and sisters, cousins (though beware, that term can be used interchangeably with nieces/nephews etc), locations of individuals, names of properties etc etc. It might involve looking in turn into those relatives' wills etc in the hunt for clues (don't even necessarily ignore 'kinsmen' or apparently unrelated trustees/execs). There will be dead ends and wrong turns, but believe me it's worth the effort.
If you haven't already come across it, there's a comprehensive index of Cheshire wills on the CRO website -
http://archivedatabases.cheshire.gov.uk/RecordOfficeWillEPayments/search.aspx It doesn't do vague or approximate searches on surnames: eg searching on surname Daniel will not also find Danyel, but searching Dan on the other hand will find both Daniel as well as Danyel and also surnames containing the syllable dan anywhere within.
You can order copies of wills from CRO, but a sub to FindMyPast
might be a cost effective option as it includes access to images of the wills as well as Cheshire parish records. The wills index on FindMyPast has shortcomings, but used in conjunction with the CRO index it's possible to refine your searches to something reasonably manageable.
Happy hunting
Birtle