The indefatiguable Robert Hughes (great-nephew of Lionel Britton) has sent me census return details for a house in Winnipeg in 1911. Among others living there are Frank Thomas (born in in France in about 1876), his wife Gertrude (née Morris at Crabbs Cross near Birmingham), and their sons Samuel (11) and Cecil (4), both of whom were probably born in Redditch, again near Birmingham.
It is perhaps Cecil Thomas who is the most interesting to me because in 1964 Britton went into business with a Cecil Thomas (quite possibly the same person mentioned above) and an Adam Stanley Keith of 320 Tweedsmuir Road, Toronto, Canada; they were the three partners in the Park Group, designed to publish all of Britton's unpublished manuscripts. They had lofty visions of Lionel's name in prominent lights on Broadway, even of films being made of his plays.
They sank. Without trace?