"I tried to play the character that since she's married to a doctor, I thought she could help put him through school and she sacrificed her career because she loved music and she wanted to be famous and sing -- but then she had Santana and dedicated her life to her," Estefan tells The Hollywood Reporter.

The back story, Estefan says, explains why Santana's grandmother is such a hard-ass -- having rejected her granddaughter after she came out as a lesbian earlier this season.

"[Maribel's mother] was a really tough cookie and probably told her, 'You've got to get a job because you have a daughter now and you can't be looking for fame or following your music,'" she says. "Maybe she squelched her dream there."

After forsaking her career, Maribel wants the best for her daughter during two key scenes in Tuesday's "Goodbye" episode, when Santana joins Rachel, Finn, Kurt, among others, when they move on from Lima, Ohio. With a scholarship to the University of Louisville on the table thanks to Sue (Jane Lynch) and Santana's girlfriend, Brittany (Heather Morris), Santana isn't totally sold on the idea and, like her mother, wants to be a star.

"They're graduating and they've got decisions coming, information is coming to me that [Maribel] didn't know and to another person that's kind of shocking," Estefan teases. "Maribel is a typical supportive mom and didn't get to go to college, so she wants Santana -- like I want my daughter -- to go to college. She had to put her dreams second and she doesn't want that for Santana, she wants her to be educated and the best that she can be."

Part of that undoubtedly will entail helping Santana make the tough decisions about her future -- and how it could potentially impact her relationship with Brittany, with Estefan noting that there is a conversation about their relationship that opens up other questions.

"Maribel thinks a relationship at that age is going to tie you down to some degree, and as a parent, you want your child to have time to blossom," Estefan says, noting she responds to her daughter's dimwitted partner in the same laughable way everyone else does. "It's tough to start that early in a relationship but you want them to feel loved and to experience that; all that is going through her head."

Estefan, who is OK with not singing during the episode, says she worked backwards to create her character who, like Santana, has that snarky, sarcastic vibe. "The apple cannot fall far from the tree," she says. "[Glee co-creator] Brad Falchuk [who penned the episode] and I were very much in sync about who Maribel Lopez was."

The performer -- who next has the CW's music competition series The Star Next Door due in the summer -- says she had a blast filming and would love to return to "have it out with that grandma."

"That would still be relevant," Estefan says, noting she put a bug in Falchuk's ear about returning to resolve the story line. "I'd like to ask her what her reasons were for saying what she did. Since I'm the woman's daughter, I know her well so we've got to talk about it and I'd love for it to be in Spanish with subtitles, or at least a big chunk of it. I think we need to see it."