Major Story Arcs
Dolly Donahue was the housekeeper for Patsy Walker's mom, Dorothy. Patsy became estranged from her mother, who was a classic "stage mom" for her daughter's career as a model and comic-book subject, so she didn't see Dolly for a long time.
However, when Dorothy dies, Patsy reconnects with Dolly. At first there is tension, because Patsy associates her with her mother, and Dolly doesn't approve of Patsy's identity as Hellcat.
When the Defenders move in to Dorothy's home as their new base, Dolly stays on as the housekeeper and cook. The house is later destroyed, but Dolly stays with the team as they move into a succession of new bases. She becomes a stalwart supporter and confidant of the team, building chatty relationships with many of them. In fact, after Patsy gets married to Daimon Hellstrom, she says she'll send for Dolly to live with them, but in fact Dolly ends up staying with the team, even with Patsy gone.
She builds a particularly close relationship with Gargoyle, who has the soul of an old man in a demon's body. Although it takes a while for her to accept his demonic form, their shared age connects them in a team of otherwise younger people, and they share a deep bond.
Daimon Hellstrom later says that she died of natural causes not long after the Defenders disbanded.