Namesakes
American First Ladies:
1 first lady
Margaret Taylor (a.k.a. Peggy) 1849-1850 
Fictional Characters from Song Titles:
2 characters
(character) Peggy Sue 1957; 1959 Peggy Sue; Peggy Sue Got Married
(character) Peggy 2011 Peggy Sang the Blues
Fictional Characters from Television:
4 characters
Peggy Bundy 1987 Married... with Children
Peggy Hill 1997 King of the Hill
Peggy Fowler 2000 Mysterious Ways
Peggy Olson 2007 Mad Men
Notable Actors and Entertainers:
4 actors, 1 model
Peggy Ashcroft 1907-1991
Diana Serra Cary (a.k.a. Peggy) 1918-2020
Peggy Cummins 1925-2017
Peggy McCay 1927-2018
Donyale Luna (a.k.a. Peggy) 1945-1979
Notable Musicians:
1 singer
Peggy Lee 1920-2002
Oscar Award Winners:
1 actress
(actress) Peggy Ashcroft 1985 A Passage to India