Wills vs trusts – help!?

My brother-in-law died and left two adult daughters. My wife and I are close to one of the daughters. I found him in the home dead; we were close. Niece and I found a will naming 2 brothers executors; buy medicine online without prescription but, then found a TRUST, naming me and his girlfriend as trustees. Girlfriend is #1 trustee, I am #2. The other daughter came in from across country for the wake & funeral. First time two sisters have been together in 20 years. My brother in law left EVERYTHING to the daughter that stayed near; the one my wife & I are close with. The only people who know this are me and the other trustee, as well as the 2 executors of the will.The will is invalid now, because of the trust. The executors are PISSED. They are blood relatives, and me & the girlfriend are NOT.Girlfriend is going to back down because she feels terrible about one daughter inheriting nothing. I would assume that I would now take over.BUT, the 2 brothers want to take over. What will happen?