Perfectly possible. If I have found the correct Frank he has two sisters listed in the 1901 census.
Living at Coventry Road, Fillongley, Meriden, Warwickshire
Parents George and Sarah, sisters Jessie (1892) and Mary (1896).
Registration district Meriden
Archive reference RG13
Piece number 2895
Folio 24
Added - Both girls are still single in the 1939 Register so either of them could have had John and his uncle and aunt looked after him.
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