I was under the impression that Tahlia, Talia, and Talya were all variant transcriptions of the same Hebrew name (Thalia is a completely different Greek name). I don't believe any transcription is "more correct" than another, though a Hebrew speaker would probably be the best person to ask. Tahlia is probably my favorite of the three, because its pronunciation is most obvious (TAHL-ee-uh).
Ayelet is a total GP of mine. And Ayelet & Talya, imo, make great twin names.
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