Child Health Specialty Clinic

Earlier today Aaron and I took Quentin down to Ottumwa to a Child Health Specialty Clinic. The lady we met with asked a bunch of questions about his eating habits, development milestones, etc. She watched how he played with toys, how he ate and drank and did doctor-y things like look in his ears, eyes and mouth. She then proceeded to tell us what Q's pediatrician did: either he is not consuming enough calories or his body is not processing the calories he consumes properly. Thanks so much. So far completely unhelpful.
On the up side they had us do a 3 day food diary of what Q eats and drinks and they are going to pass it on to a nutritionist. The nutritionist is supposed to get back to us in a week or two with her findings. I really hope she actually has something useful for us to try, cause I don't know what to do anymore.
In the meantime, we're to add butter to everything we can, try to get him to drink more whole milk, and see if he'll drink any shakes or smoothies.