I have small kids

They weren't born small. (T was 8lbs 2oz, D was 8lbs 7oz) They both eat well. They are just small.
When T was a year old her pediatrician asked me to try to make her gain weight. We increased her caloric intake and she gained enough to get back on the growth chart. And the pediatrician was happy.
Ever competitive with her sister, D managed to get the pediatrician to tell me the same thing a month ago at her 9 month well baby visit. Weighing only 15lbs 6oz D needed to gain weight.

Flash forward to today.
I haven't slept. I've barely slept all week. Baby D wants to nurse every 1-2 hours at night. Last night she didn't want to be put down. She screamed all night, nothing I did helped her in anyway. At 6:30am I had to give it up and let her cry. I hate that I did it. But I was so worn down from the entire night of it. I told my husband that we would call the pediatrician in the morning. By 7:30 hubby got up with her and I actually managed to get a little bit of sleep. At 9am I called the pediatrician who fit us in at 9:45.

The first thing they do at a pediatrician visit is a weight check.
After a month of stuffing D full of fattening foods (She ate so much tuna casserole the other night that I watched my 10 month old almost pass out in a baby carb coma.) it was finally time to know how successful we were. The moment of truth.
Fifteen pound and seven ounces.
I was floored. Nursing every hour at night, eating a diet of cheese, french fries, pasta, baby food...
She gain an ounce. ONE. In a month.

The pediatrician figures the sleeplessness and general jerkfaceness is because she's got 4 teeth coming in. But the weight issue has gone from a we'll keep an eye on it to a we're going to have to see a specialist.

To start we need to do some blood tests and a urine analysis. So after a long night of screaming all night Baby D got a catheter and a blood draw.

And then a nice long nap in the car.