None of the four Diana Stanley births from 1915 to 1940 have Brocklebank as a mother’s maiden name, so she may well have been born in Scotland or Ireland or abroad. The web site
ThePeerage.com says she was born on 10 Nov 1927, citing BLG 18th edition (of 1965?).
But The Times has this notice on its issue of Weds 16 Nov 1927:
Stanley -- On Nov 10 1927, at Karachi, India, to Sandy, wife of C S Wentworth Stanley--a daughter.
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