If your ancestor refused to answer the door for the census taker, neighbors may have answered questions for him. Their knowledge may have been sketchy. If your ancestor was in a boarding house, the landlady may have answered questions for him. And it’s possible that your relative was missed by the census taker entirely. It’s unusual to be missed if a person was “stable” and not moving frequently. Movers and people avoiding the law tended to sometimes avoid the census taker.
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