My grandmother's hidden relationship with a U.S. Marine in Derry

Contributor's grandmother - Elizabeth Claire Muldoon -
Irish Street, Derry (WW2), Waterside, Derry.

Big U.S. Marine presence during WW2 - letter sent about seeing a dance (with U.S. personnel and local girls).

U.S. Marine, Clarence Emery Dicken - [also mentions a "Michejay Gladwin" - suggests a relationship and 'child born' (mother) - letter addressed to grandmother on U.S. Marine Corps letter-headed paper.

Never had children when he returned to U.S. - married his childhood sweetheart.

Mother left clues with modern family about 'Clarence' and the fact he 'never married' - surnames were used.

Contributor (Stephen) has met extended U.S. family (descendants).