Recently Had A Sister Inlaw Die Of Kidney Cancer With

Recently had a sister inlaw die of kidney cancer with spinal Mets and there is a great problem with her will.she changed her will while taking strong pain medication and also anti depressents I'm just wondering what effects the combined drugs may have effected her. By the way we are not wanting anything from her estate but consecently she left her estate to people she has not known for long,not her children !!!!