sounds like nails on a chalkboard to me (it's the harsh S combined with the fee-sound), sorry! I think it's a name that is loved by many, though, so I'm sure most kids would love to have it. I just don't care for the sound. Sienna
is soft, pretty and less common so it's what I'd go with. I don't like the Sienna
Miller association but it seems to fade now that more and more girls are named Sienna
. I also like the color.
Personally I think yes, she's too young to honor. Naming a child after her would be like naming your child after her older sibling or something. I don't know why I feel this way, but it just seems a little odd to me.
But she's your daughter so you have to decide what works. If you want to honor your sister, you should.