What should be our next move?

[Romersgirl]

Soc you have helped me out a few times with custody and I thank you!

Background:  BM decided she didn't want to be a mother anymore so she would give my soon to be step kids up.  However she would not give them up to us, she would give HER custody up to her mom.  On the advice of our att. we let this happen bc he said it was easier to get custody from a 3rd party in lieu of the bio mom.  Well this was about 3 months ago. In that time she has only seen the kids a few times and does not stay involved.  We are discovering problems with the younger child and starting to getting him evaluated for learning and behavioral disabilites.  

Before she signed them over (which took about 4 months to actually get done) we had abuse charges on her boyfriend.  Social services found the charges to be founded however the judge dropped them.  She has now married the man, there is currently a court order preventing him from being around the children.  My problem is she is talking about trying to get them back.  The papers are drawn up that BM as joint custody with my finance, while physical custody with the grandma.

1.  It is now in our favor that she has married the man who has abuse charges on him for the children, correct?

2.  We do not want her to get these children back full time, how can we prevent this?

3.  Should we file for immediate custody?

4.  What chances does the grandma have for keeping physical custody?  

5.  Since the papers are drawn up that the mom still has joint legal custody, who has say so, the BM or the grandma?