Hi and welcome. Thank you for joining, and for reaching out to our community because we're here to help. What's your dog's name? He's such a lucky dog to have you for a parent. You ask some great and important questions, and we hopefully have some things you can consider.

First, I moved your post here from coping with loss because based on what you wrote, I kinda feel that what you are describing is not a dog who is ready to say goodbye yet, especially what you shared in your other post about his recent diagnosis. Yes, all Tripawds will face mobility challenges eventually. It is the price of having an altered gait, and unfortunately there's no way to get around it. But, that doesn't mean the situation, when it does happen, is hopeless.

One of our primary missions here at Tripawds is to ensure that Tripawd cats and dogs grow up with a safe, protected lifestyle so that when those senior mobility issues occur, they aren't as severe. We recently wrote this blog post I think you will find helpful:

Arthritis and the Senior Tripawd Dog: Wyatt’s Story (so far)

Also, this interview with the renowned animal rehabilitation therapist Sasha Foster may also give you some insight:

How to Help Aging Tripawds Live Better

So, I guess my main question to you is, has he been evaluated by a canine rehabilitation therapist yet? If not, we can help with that: the Tripawds Foundation may pay for your first rehab visit , just click on the link for more details.

Oh and to answer your question:

At what point do you think mobility becomes a reason to say goodbye to your dog? 

Every dog is different. To some, when it's time for wheels it's time to say goodbye (not me). For others, when the dog can't stand or potty on their own. It all depends. A canine rehab therapist is one of the very best people help you asses whether or not your own dog's quality of life is lacking so much that it's time. Oftentimes, once a dog or cat's pain is better managed through rehab and pain management , they go on to enjoy much more time with their people. It's amazing what we  have seen it do to give a Tripawd their quality of life back, even the seniors.

I know you're also dealing with the spleen issue, so I'm going to go over there to offer that kind of feedback. And thank you for posting in two separate places, it really helps!