There was a Robert Corlett, mariner, in the Maughold parish register:
Marriage:
23 Jun 1872
Robert CORLETT, Full age, Bachelor, Mariner, Kerroo Muir, Lez., [father] Thomas Corlett, Labourer, and
Elizabeth COWLEY, Full age, Spinster, Mona St, Ramsey, [father] Robert Cowley, Labourer.

Two children bapt Lezayre 6 Oct. 1872 (twins?). Emma Isabella & George Alexander.

If he had an illegitimate child, he (and Ann) may appear in the Presentments (at MM).

Brian Lawson's burials:
CORLETT, Emma Isabella 64 Lez 12 Sep 1936.
CORLETT, George Alexander 81 Lez 29 Mar 1954.

Re. John's death date, this could be his will:
CORLETT, John 1916 Pee 152 0106588

There is one for a Henry Corlett, which might answer a few questions, if the right Henry:
CORLETT, Henry 1895 Ram 240 0106522
Maughold burial: Henry CORLETT, 54 yrs., Ramsey, 3 Dec 1895.

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