Just one of those things, I guess. He made it through the critical period (first 48-72 hours) without any red flags showing up, and then he just drastically went downhill. The vet couldn't find any physical reason for it. For a while we were keeping him warm and hand feeding him, but it just wasn't enough.
I'll take individual pics of the pups the beginning of next week. They are growing FAST!! And Teeny continues to be a fantastic momma.