Sorry for your lose.I know how you feel.We went thru the same thing with our shorthair Lazy,he was 15 years old,and getting down in the hips.I,m sure he went down in a ditch and could'nt make it back out.The last time we hunting i had to carry him up a terrace that was to steep!!
We looked for two days and never did find him. I take comfort that he was doing what he loved to do. HUNT!!!!
So sorry again!