Definitely
Sylvia, as it's my mother's name and my personal favourite out of the variants.
Sylvie and Via are good nicknames. I would consider actually using this.
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LISTEN TO THE MUSTN'TS
-
Shel Silverstein
Listen to the MUSTN'TS, child,
Listen to the DON'TS
Listen to the SHOULDN'TS
The IMPOSSIBLES, the WON'TS
Listen to the NEVER HAVES
Then listen close to me—
Anything can happen, child,
ANYTHING can be.