I have two sibling boys who are nearly seven months old. One weighs 7lbs12ozs, the other 8lbs8ozs. That 12ozs difference makes a huge difference, the smaller one has noticeably smaller and finer bone structure and you can feel his ribs and I'm wondering if he's always going to be this way or if he'll catch his brother up. The other definitely has a good coating of fat and is much stockier in face and body. It'd be good if they were both somewhere in the middle.