After being introduced as the daughter of the man who killed Dick Grayson’s parents, she’s part of a villainous cabal that’s taken over Bludhaven, which the former Robin just rededicated himself to cleaning up.
However, Nightwing #81 reveals that the titular hero and Melinda have an even deeper connection than he could have expected.
https://www.cbr.com/nightwing-melinda-zucco-sister/