the earl s mother, hon. sarah archer (1762-1838), countess of plymouth & countess amherst of arracan, after andrew plimer. memorial 6th earl of plymouth @ st bartholomew s church, tardebigge he born son, , had 2 sisters lady mary windsor, married marquess of downshire , lady harriet windsor, married hon. robert clive, son of earl of powis , grandson of clive of india. styled lord windsor birth, inherited titles father on 12 june 1799 @ age of ten, along father s land @ tardebigge, country seat hewell grange, , land in shropshire , glamorgan. year later (1800), mother married lord amherst first wife, , bore him 2 sons. not clear if young plymouth grew stepfather (but highly likely); if so, exposed influences of amherst s wide-ranging court , political connections, culminating in failed (1816) embassy china. plymouth educated @ harrow. he married lady mary sackville (1792–1864), elder daughter of john sackville, 3rd duke of dorset on 5 august 1811. there no issue of marriage, , lady