One of the lessons that Josh and I learned the hard way came with our second adoption, little Amanda from Korea.
Amanda came home from Korea at almost two years of age, and she was escorted to us, so the entire family went to pick her up at the airport. Since we live three hours from the airport, we decided to stay a night in a hotel so we could have fun getting to know each other without the long drive.
Amanda came with a bag full of goodies, including bottles and formula. Since the formula and the instructions were in Korean (which I do not read real well), and since we already had milk for Maggie and we figured that since Amanda was almost two she didn't need baby formula any more, we just filled up her bottle with milk like we did with Maggie's.
Amanda took the bottle, took a sip and then happily drank it, and Josh and I congratulated ourselves on making a good decision, until she threw up all over the car.
We heard her make this really soft noise, and then she gave us this look like, "You are really nice people and I am really sorry to do this, but..." and then she threw up everywhere.
Silly us, we blamed it on carsickness, because we knew she likely wasn't used to riding in a car. The next morning we were sitting down to the free buffet breakfast at the hotel and Amanda was eating well and drinking her bottle when she gave us that same, sad little look, and then threw up all over the table.
Josh said, "Do you think it could be the milk?"
We got some American baby formula and slowly transitioned her from formula to milk, and wouldn't you know it, there was no more projectile vomiting.
I should have known better. I knew that with babies you should always change their diet slowly. Heck, I even knew that with dogs you are supposed to change their diet slowly. For some reason I thought that the two year old would be just fine. Not so much.
It has become a running joke between Josh and I, every time we have a new addition one of us will say, "Should we give him bottles and bottles of whole milk??" :)
We learned that if you are going to change your child's diet, you should do so slowly and gradually. Lesson learned!