Dream interpertation is interesting. I can tell about dreams I have had before major events in my life. I dreamt of my father's death and then again when his best friend died. I had several dreams before the attack of 9/11 and before my eldest daughter was born I had a dream of her watch her sister being born. I had dreams about running away from a man that crimminaly stalked me and the list goes on. As to what this dream means to you is difficult to understand with the information you have provided. Dreams like this one you have had usually for tell of an event into the future. I have never been given more than 72 hours notice of the event. Except for 9/11 that was a week of sleeping terror. Look into the odder and simple portions of the dream that is usually where I find the clues to the answer. When my father's best friend died I dreamt of being at a carnaval of sorts with my best friend and some very odd circumstances took place where she threw me the keys to her car so I could make a get away and as I drove away from the high school I went to and my parents and their friends her car became smaller and smaller and could no longer be driven and then the road ended. The symbols I am talking about were best friends, the school, the yellow car (there was a yellow VW Beetle in my fahter's past), and then then end of the road where I could no longer drive. I hope this helps you in finding the clues.
This must be very difficult for your family and I wish you all the best in your search. I wish I had a clearer answer for you. But I feel the answer lies within you. You may dream again and sometimes it helps to write down the details so you can remember them clearly. Good luck and if I can help in any way further I am at your service.