my baby is 9-mth old and he weighs only 18lbs. It's 10% and also 10% on height and head-circum. He was used to be (weight-height-h.c.) 25%-75%-75%, 50%-75%-50%, and 25%-50%-50% at birth, 3-mth, and 6-mth. I don't expect him to grow over 50% line or anything but at least I hope he stays where he is now. I am afraid if he is not growing well because of some other reasons and will be afraid to check all those numbers at the one-year checkup. I was breastfeeding 100% until he was about 8-mth-old but now about 60% because of declining supply (I'm working full-time and expressing milk). He also has severe constipation. Other than that he is very healthy and does everything any 9-mth-old should do. My family and I are on the 'big' side and my husband's are on the 'mid' side, both weight and height. Should I be concerned? I heard that after 9-mth, a baby gradually shows his genetics. Does he still have a chance to grow over that THICK 10%, 20%, or even 50% line?