Sheila is older than Lorraine. Sheila is my mum's era and she's 89; Lorraine is mine and I'm 65.
Mum's friends are/were: Barbara, Silvia, Patricia, Marian, Anita, Joan
Mine, and classmates: Susan, Jane, Helen, Alison, Deborah, Karen, Amanda, Fiona, Carol, Caroline
DD (27): Alice, Imogen, Rosie, Tilly, Molly, Cicely/Cecilia, Isabel
Obvs, there's always a bit of crossover and I have known a couple of Sheila's of my age, but both have been Shelagh.
Names have always gone in cycles: the ones that mostly transcend time imo are: Helen/a, Catherine, Elizabeth, Hannah, Caroline, Anna/bel, etc.