Sorry to hear about Penny, Kevin. I know exactly what it feels like to loose a dog. Hope you and your bro are doing OK.
This subject has been crossing my mind alot lately. My dog had his tenth birthday this year (well, we THINK it's ten, since he was a pound dog, the vet only could guess at his age. Personally, I think he's older) but just since December he has aged quite a bit. He went completely deaf just before Christmas, his eyes are getting cloudy and he has a hard time seeing at night. Now it looks like he's getting arthritis in his front legs and has a hard time on stairs and even just lying down is tough. We used to go on up to four or five long walks EVERY day. That's now been cut down to maybe two or three short walks, depending on how he's feeling. Sometimes, just by how he's acting, it looks like he's just plain confused and gets quite crabby which is something he never was before. Then again some days he acts like a puppy but I know what lays ahead so we'll make his last months (who knows, maybe years) as comfortable as possible.
It looks as if Penny had a damn good life.