In 1976, Phoebe Tyler was so desperate to keep her son, Linc, from remarrying Kitty Shea, whom she considered beneath his station, that she paid off Myrtle, an ex-carnival worker, to pass herself off as Lucy Carpenter, Kitty's long-lost mother. Myrtle came to love Kitty, though, as the daughter she’d never had, and began to resent the scheme. The scam collapsed when Mona Kane paid her old friend "Lucy" a visit and immediately knew that Myrtle wasn't who she claimed to be. Although Myrtle had her pal, Nigel Fargate, pose as a doctor and tell Kitty and all of Pine Valley that "Lucy" had passed away, Phoebe got drunk one night and blurted the whole sordid story. Kitty and her substitute mother were happily reunited.

Kitty left Pine Valley in 1979, leaving the care of her shop, the Boutique, to Myrtle, and Myrtle sold the shop to Ellen Shepherd in order to marry Nigel in Minneapolis. After Nigel died, she returned to Pine Valley, where she and Mona decided to invest their money in a retirement home at Willow Lake, but luckily Brooke and Edmund discovered that it was all a scam in time to save the day. Myrtle got involved with Erica after Mona died, and has acted as a surrogate mother to her at various times, including helping get her to The Betty Ford Clinic in 1996 when Erica was addicted to painkillers.

Also in 1996, Myrtle was involved with Red Kilgreen, who may have been Santa Claus, and reunited him with his wife just in time to save Christmas.

Myrtle is much loved by the people of Pine Valley, and many have benefited by her wise counsel. She also runs a boardinghouse, housing most of Pine Valley at one time or another. She recently discovered her long lost daughter, Rae Cummings.