I think she's in her late 30s.
Don't forget that Glossy mentioned Eclipsa in Pageturner. He said that Eclipsa was the only queen who didn't try to interfere with his teaching.
This would mean that Eclipsa's pure-Mewman child was at least 14 years old (because that's the traditional age a princess gets the wand) and had some time to learn with the wand.
So let's assume she had her first kid at 20, and eloped with her monster husband when the kid was 15. And then she had to have Meteora and was around while she was in her swaddling stage. We don't know how old Meteora was when Eclipsa got frozen though.
Assuming Meteora was still an infant when Eclipsa got put into a crystal prison, who was taking care of her? Her father? She probably left (or was taken) from that room in the monster temple at a very young age, otherwise it wouldn't still look like a baby room.
If we get a flashback to Meteora's childhood, maybe we'll meet the actual Saint Olga? >>98115219
Marco's kid comes from the future, but happens to have traits from Star, Kelly, Hekapoo, etc, so nobody know who the mother is. It all turns out to be a ruse and Marco Jr is just a shapeshifter or something.>>98121263>tfw no Ludo in the City episode where he crashlands in Echo Creek and has to find a way to return to Mewni >>98122148With Star as a conquistador, right?