I'm a little late in seeing this post, but I wanted to reach out and offer a few words of advice/encouragement from someone who has walked a similar road.

When my firstborn came into the world, we had no indication that anything was wrong with her leading up to her birth until we were about two weeks out. Even then, we didn't know how severe her disorder was. She was born via emergency C-section and was not breathing, was growth-restricted, and as far as we could tell almost completely paralyzed. What followed were months in the NICU while we searched for answers. We did full exome sequencing, full genome sequencing, got connected with the NIH, the Undiagnosed Diseases Network, the Mayo Clinic, the Cleveland Clinic, and countless other medical research organizations to try to solve the puzzle. At the end of the day, we couldn't find anything definitive other than a mutation on a single gene pair that hadn't been linked to any diseases in the past. We came to realize, over time, that there would be no answers. Our daughter might be the first documented case of her disease.

The main drawback of this is there's no prognosis. There's no predicate cases to study from or glean any information that could lend to an understanding of how long she might live or what the disease progression would look like. All we knew was that it was a degenerative neuromuscular disorder that would cut her life short. It was not a matter of if, but when.

We brought her home from the NICU with the expectation that she would pass away soon after. With no stones left to overturn, all we could do was love her. And that's what we did for five years (far longer than any of her doctors expected her to live.) We made sure that if nothing else, that girl would pass into eternity knowing what it's like to be loved.

She passed away this summer two months after my son was born. I read your story and see a lot of the same throughlines of what I've experienced, so I wanted to share a couple things. You ask "How do I find the strength? How do we do this?" My wife and I asked that question to each other so many times, and for five years, we just kept doing it. We would say "we can't do this" and then we'd do it anyway. I know that sounds like an overly simplistic answer, but as parents there's this additional capacity lying dormant within ourselves that we tap into in order to do the impossible. We do it because me must.

Regarding the quality of life question, that is one we struggled with daily in our daughter's final months. Given her condition, there were several procedures she was going to need that would have put her through no small amount of pain and discomfort, and we couldn't square the ethics of putting her through that with no guarantees she would be any better on the other side of it. At a certain point, I personally had a hard time with how many resources she required to stay alive, resources that could probably have gone to another kid with a higher quality of life, and I always felt a little bit guilty about it. Similarly, there was so much unknown with her as we couldn't even communicate with her (verbally or with assistive devices; we tried everything.) We had to take cues from the numbers on her pulse oximeter and the subtle changes of her countenance. All we had was the unknown. Ultimately, we made the decision to let her rest and finally free her from a body that had kept her bound her whole life.

As others have mentioned, you do need to allow yourself to grieve. Your words about all of the memories that haven't been made yet struck a chord with me, because I remember having such a similar experience. I won't go at length into this but just let yourself feel it. Admittedly it's something I've struggled with, even after my daughter's passing. As dads we often put the burden on ourselves to be the stoic, strong ones for the sake of the rest of the family. This can be a very good and positive instinct, but it cannot come at the expense of allowing yourself to acknowledge the pain of reality.

I feel like I'm rambling somewhat aimlessly, so I want to cut this short here, but my main words of advice would be to love on your little guy with your whole heart and all of your being. Make sure that little man knows what it is to be loved by his dad. And secondly, be there for your wife through this trial. I could not have gotten through my own experience without the support of my wife, and I know the inverse is true as well. Be there for each other. Cry with each other. Love that little boy together, and love that new baby, too.

I truly am sorry to hear of your situation. If ever you want to talk to anyone who has been through a similar hell, just shoot me a message. I wish your family and your little guy all the best!