W.O.
My dd was that way. She is still so young, time outs or other consequences like that I don't believe will help, just cause more frustration. Especially with a spirited personality. It is important not to break their spirit, these are personalities that will someday really be an advantage to them provided they are allowed to learn how to work with them. I think the best thing to do is to understand where she is coming from and show her what you do want her to do. How to trade items, how to take turns, how it makes others happy when she does this, etc.
To help me understand my dd when she was toddler, I printed this out and put it on my refrigerator. It made me smile.
Toddler Rules
1. If I like it, it's mine.
2. If it's in my hand, it's mine.
3. If I can take it from you, it's mine.
4. If I had it a little while ago, it's mine.
5. If it's mine, it must NEVER appear to be yours in anyway.
6. If I'm doing or building something, all the pieces are mine.
7. If it looks just like mine, it is mine.
8. If I saw it first, it's mine.
9. If you are playing with something and you put it down, it automatically
becomes mine.
10. If it's broken, it's yours.