Martin P-L writes:

Anne and Jane lived  together in Conduit St., Hanover Square, unmarried.  They both died at Lilford, Jane in 1782, aged 90, Anne in 1777.
An Anne Powys married a Thos. Harwood at Bitterley in 1723, but I do not know who she was.
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Her baptism was found in the Register of St Giles in the Fields, High Street, Holborn on the page for May 1693:

“14  Jane of Sr Thomas Powys Knt & Sarah his wife.  Born ye 11 Inst.”
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See her Mon Inscr Notes for her death info.
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Will of Jane Powys, Spinster of Saint George Hanover Square , Middlesex 25 September 1782 PROB 11/1095

From the Northants FHS booklet of Mon Inscriptions for St John the Baptist, Thorpe Achurch, pub 2015:

On a black marble ledger stone:
“In memory of Mrs JANE POWYS, third daughter of Sir THOMAS POWYS, Knight, who died September the 9th 1782 aged 91.”
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