Liz, before you started looking into your family history, did you grow up knowing your grandparents, Robert Henry Cain b 1894 and Elizabeth alias Race nee Beatty b 1892 ? Were you aware of a great aunt Lydia ( wife of Richard Kennaugh ) who was a sister of your grandfather ? And a great aunt Alice (wife of Mr Clarke) ?
If the answer is Yes, then the Robert Henry Cain age 17 found by Averil in the 1911 census in Douglas is definitely yours. The connection to Lydia definitely clinches it.
The Edith who was the single mother of Lydia b 1889 was a COWELL, as was the Edith who was the mother of Robert Henry b 1894. And the Edith who married the John Cain in Douglas in 1917 was also a COWELL.
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COWELL, Alice Maud Mary 7 Oct 1886 Douglas 607 Not given COWELL, Edith Ann
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COWELL, Lydia 4 Dec 1889 Douglas 810 Not given COWELL, Edith Ann
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CAIN, John Robert 13 Feb 1893 Douglas CAIN, John Henry COWELL, Edith Ann
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CAIN, Robert Henry 22 Apr 1894 Douglas CAIN, John Henry COWELL, Edith Ann
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I've been thinking about that 1917 marriage of a John Cain to Edith Cowell. From John Cowell's 1908 will, his daughter Edith , although living with John Cain as his wife, was still Edith Cowell. My guess would be that something triggered the need for John Cain to "make an honest woman" of Edith. Maybe everyone just assumed that they were married, but then perhaps Robert discovered that they weren't, in the lead up to his own marriage to Elizabeth in 1919, and he requested that they "legitimise" his birth. What religion were they ?
Jean C