Colin did end up having to go back to the hospital for about 4 days in January. He did re herniate, but the surgeons wanted to hold off on surgery as long as they can since "he was doing so well." We figured out a feeding regiment that works for him and as long as we stick to that, he doesn't throw up at all. This is a huge development!
He has started to pick himself up onto things and walks around the couches by holding on to them. He is also crawling now, so he is always into everything and all over the place! It's just a matter of time now and he'll be walking!
We are still going to a physical therapist once a week and he seems to be responding to the treatments well. We have literally hours of work we have to do with him at home, in between sessions. It's a lot of work, but the payoff is going to be awesome!