Some TMNT stuff was always meant for grownups.
Gabrielle Jones was briefly the wife of Casey Jones and the mother of Shadow in the Mirage series. Not much is really known about her, including her last name. She met Casey as a waitress after he left New York to get over his rejection from April. She was affectionately called "Gabe" by him. The Image continuity, this was retroactively changed to "Gaby".
In the Image continuity, additional backstory was written for Gabrielle. Like the rest of the Image continuity, these details expand the preceding Mirage continuity, but were disregarded by all Mirage canon that followed.
At least a year before taking her job in the café, Gabrielle was involved with Albert Puzorelli, an Italian man with strong connections to the New York mob under mobster Antoine Puzorelli. It quickly ended as he dumped her before he died; it's never stated if she knew his family's business or of his future death. Either way not too soon after he dumped her, she discovered she was pregnant.
- Its never explained why or how Gabrielle became involved with Albert.