Natassia is a completely legitimate version of Natasha. Just because it's not the normal version given in English speaking countries doesn't make it less real. Natasha, Natashya, Natasia, Natassia, Natasja, the list could probably be longer but I can't be bothered.
Glad you liked one of them, I tried to find names that would fit your style, but I might've taken it too far... ;)
I think Jessamine fits the best with your other daughter's name. I also think that Jessamine has a more universal feeling to me (as in I don't have a distinct image of who a Jessamine is). I'm not familiar with Natassia but because of similar names it felt very eastern european to me (not a bad thing, but more specific in my mind). When I looked it up though there were a lot of posts on a Norwegian Nastassia (who is also part Malaysian). But I digress. I'm biased because I LOVE Jessamine and think it's gorgeous, but I also just think it fits better.
Otilie! I think you both could be right. Traditionally Russians probably did use Natasha as a nickname, but today probably a few of them are given it as full name, the same way American (and other nation's) girls are given names like Tess (Teresa), Molly (Mary) and Sadie (Sarah. Also in American a lot of Russian diminutives have been use probably incorrectly as full names including Natasha, Sasha, and Misha (some of which I am aware are boys names). I would say these are sort of multicultural names. Finally On Sex and the City, Big's wife was named Natasha and I am unaware of her having another name besides Mrs. Big.
Since Sepphiria is a long, rare, ornate, 4-syllable girls' name which is a variant on the more common spelling (Sapphira), Natassia matches perfectly on all those counts.
However, I think they're too matchy. I think you're painting yourself into a corner a bit. I like Jessamine, which is very feminine and floral without being frilly. It's long and rare and formal, like Sepphiria.
Frankly too I don't like the prominent 'ass' in the middle of the name.
Perhaps you could change up the middles since neither Lyric nor Skye has meaning for you? Jessamine Willow Sage, Jessamine Opal Sage, Jessamine Nina Sage?
I much prefer Jessamine
My DH was watching a movie and an actress from it was named Natassia. He instantly fell in love with the name! I am still more for Jessamine, though.
@Blade - Willow and Sage are on our list for middle names, but I was told that Pink named her daughter Willow Sage, so that combination would appear that I'm trying to mimic her.
Sasha everywhere but officially his name is Aleksandr for sure. They may never use their full name but have it in passport.
Using a nickname as a full name is popular in US and, of course, there is nothing wrong, but you can't say Nastassia is a Russian given name. Anastasia, for sure, but Nastassia sounds all American to me.
I am not against Nastassia, but you should know it isn't a Russian full name. Actually Annouchka, Mashenka, Sasha, Fedya etc are not given name too. But since we are in US(UK, Austarlia) ,use the name you like.