It is a good question. My heart is with you darling... Im not too sure what I think also, but somehow I think the spirit lives on, especially in our hearts. My heart is breaking also, my sister passed away Nov last year. I have three sons, one 26 also, I cant imagine the pain of that.
I'll tell you a story, ok;
My pain has been so deep, I cried every day. I think alot of my tears were more so from the reason she died and why? What may have been, I think and more so that I will never share my life with her again.
One day, I decided to clean my bathroom and I noticed a shining reflection. I had to put on my glasses to see what it was. It was a crystal angel, that I had given her. I thought it had been lost in the clean up of her house but somehow it stayed tied to some soaps my mother had given her. It was a bad morning, tears and sorrow, but since this happened somehow I think it was her message to me, that she was ok. This has given me some calmness. Maybe finding your sons chip is his message to you.
Cry and cry some more sweet darling Spiritualseeker, its ok, and I send all my love to you at this sad time.
JJ