H-4 transfer question, thanks in advance!

Hi Dear all,

I have a question about my daughter's H-4 Visa. My wife transfered from F-2 to H-1B in 2007, at the same time my daughter transfered from F-2 to H-4 as dependent of my wife. I was F-1 at the time.

Then my wife transfered her H-1B a couple of times to other companies. We asked a lawyer if we need to transfer my dauther's H-4 as well. He said as long as my wife keep her H-1B visa and my daughters h-4 is valid, it is not necessary to transfer her H-4 everytime.

1. is it correct?
2. I currently hold H-1B and I want to transfer my daugther as my H-4 dependent. Because I will apply for green card and my daughter's H-4 will be expired around 08/2010. Is it operational and is it too early to do that?

Thanks a lot,