The marriage record is available from Scotlands People and will contain parents' names.
She is indexed under the surname Hanna and under McNaught.
https://www.scotlandspeople.gov.ukOSWALD, WILLIAM
MCNAUGHT, MARGART AITCHIE(son)
1946 644 / 19 / 119 CATHCART (GLASGOW)
OSWALD, WILLIAM
HANNA, MARGARET AITCHI(eson)
1946 644 / 19 / 119 CATHCART (GLASGOW)
This is possibly her birth - again available from Scotlands People.
MCNAUGHT MARGARET AITCHI(eson)
F 1925 615 / 101 STEVENSTON
Her 2002 death registration, Margaret Aitchieson Oswald (age 77), in Coventry Warwickshire gives her birth date as 5 May 1925.