I just got thru having my wife's house dog put down. He was thirteen, and was healthy his entire life. Then one day he stopped eating, and started getting weak. Turned out he had a liver infection common in older dogs. $300.00 later, no change, and now he is laying next to "Tank" a Jack Russell we lost a year or so ago.
Good luck on your old friend Arier Blut.
My wife still gets to cryin every now and then (it's been 3 months) but, now she mentions havin another one. We'll see. Ole Huff my other Jack Russell is still patroling my half acre yard, and right now that's enough for me.