The way i've learned to pray is to pray every day tht the Lord's Spirit teach me who to pray for, and how to pray for them. My opinion would be this: If they're not saved, pray for their salvation. nothing is more important. Nothing. If they are saved, pray that the Lord will comfort the grieving, and that those offended forgive the offenders.

I totally agree with ndnthomas and couldn't have said it any better.

I do first of all thank God for all things. (ephesians 5:20) I know it seems rediculous to thank God for this situation...but i do thank God for any evil i find when i find it. It isnt because evil pleases me but because I trust God. I trust God and his word and we know romans 8 and 28 which says: And we know that in all things God works for the good of those who love him who have been called according to his purpose. I often feel the same burden you are feeling. The burden you feel is from God burdening you to pray, and i think particularly over the son and his wife whos activities "seem" evil. I said seem because people grieve differently. You also have your own grief in all of this, which is obviously being compounded by ur friends son's behaviors. It would help me to have their names so i might add my prayers to yours.
FAther you know I thank you for all things and all situations. I thank you also for this. Its hard for us to handle seeing behaviors from others that we do not understand. We do trust you in all things. You are faithful. You are our comfort. You know every detail of concern in my heart over this situation, for the sisters, for the son and his wife and for your daughter who wrote this post. You know what we need most of all in this life is you. FAther if there is evil here please do not let it continue. If it is about greed please stomp it out. Dont the daughters deserve to have some momento's? If this woman's behavior is wicked God I ask you to bring her to prostrate before you where we all belong. You lift up the humble and bring down the proud God. Use this situation to bring low those who are being arrogant and lift up those who are humble before you. I thank you Father that you always hear my prayer and always respond in your power. I know I do not deserve to recieve anything i ask for. Yet your word encourages us to ask. Your love for us that you showed us throu your son our Lord Jesus and his sacrifice for us gives us courage to pray to you and ask you. Fahter I also ask you for your comfort to be poured out upon your daughter who wrote this post. All glory and honor and praise always be to you.

amen...you said everything i wanted to in prayer and couldn't find the words..thankyou joey...may God bless you...and thomas and and annie...the good news is that my friend and her husband are both with Jesus now.