I don't know why things like this always seem to happen in bunches, Janet, but they do, and it's dreadful. My heart goes out to you ... so much pain, it's just not fair. I am praying for you, your family and for Angus. He IS out there somewhere, and you WILL find him. He is making his way back to you, I am sure.
Years ago, a Sheltie was lost in the next town from us. There was a huge search but he wasn't found. Two YEARS later he appeared in the same town, and was returned to his family, a little thin, but fine. He'd survived two Connecticut winters and heaven knows what else. The story made all the papers; no one could believe it. Miracles do happen. We must believe.
Sending good thoughts and hugs your way.