Also according to the Genshin wiki, in the Mandarin translation, Idyia refers to Rhodeia as "Older Sister Rhodeia"... and I headcanon that Urania is Rhodeia's younger sibling...
So now we have a potential "Of Loch" trio here, so here me out.
Idyia, Urania and Rhodeia interacting with each other, maybe even doing some silly sibling stuff.
Oooooh I love it. (Like yeah obvs many Asian cultures use overlapping terms of endearment for family and close friends, auntie and uncle especially, but I want this to be true.)
They grew up together. Idyia was always the timid one. Bonus points if she's the oldest by a significant margin xD (yes I know that contradicts the older sister part, but shhhhhh)
Related question, do Oceanids "die" when they reproduce? "Merging water bodies together" then splitting apart? Or would they just split off an Eidolon and send it off?
Oh my gods, imagine if the Lord of Amrita was literally the mother of every single Oceanids, no wonder they miss her so much ;_;