Deed histories online in County Clerk’s office...each deed list the prior owner, so your daughter can start with the folks from whom she bought the place and backtrack. http://mcclerksng.co.morris.nj.us/publicsearch/ Looks like Marie Foote, owner/developer of Spring Brook Estates, deeded property to first owner in 1926 (though, yes, Tax Board lists 1920 as construction date). Map of the Footes Spring Brook Farm in 1910 here https://cdm16100.contentdm.oclc.org/digital/collection/p15387coll8/id/9/rec/25
I would suggest contacting the Morris County Tourism Bureau on Court St in Morristown. Friendly and extremely knowledgeable staff and historians. Worst case, they would likely be able to point you in the right direction.
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