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Re Henry missing in 1851 census, in 1861 he is correctly shown as born Illogan married to a Mary A, I checked the births of the children and they all had mothers maiden name Clements, their is a marriage of Henry Angove to a Mary Ann CLEMENS Dec qtr 1850 Redruth v9 page 294.
Searching the 1851 census Henry is incorrectly shown as born Camborne married to Mary A with a child William H aged 2 months, his mothers maiden name was CLEMENS, unfortunately he dies aged 9 months in Dec qtr Redruth v9 page 195
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