I totally don't want to freak you out here, but do want you to get DS checked out and see if he needs some help. DD had a heart murmur, and at 2 mos old we learned she had an Atrial Septal Defect (ASD)--this is a congenital heart defect in which there is a hole between the two atria of the heart. This makes the heart work much less efficiently, and a common side effect is stunted growth. DD was watched carefully for growth issues, but we didn't think she had any, since she was at 30% for height and weight, so well within the bell curve. HOWEVER, the hole continued to grow, as opposed to shrink/close on its own (which is what we hoped for, and what happens most of the time). At 6 mos. old, DD had surgery to close the hole. Within 6 weeks of the surgery, she went from 30% to 80%, and now, at almost 3, she is off the charts huge (in 4T clothes already--not fat at all, super active, but very tall and sturdy!). It turns out that her growth WAS stunted by the heart defect, we just didn't know at the time. Which is all to say--definitely get the echo done, and, if he needs help, it's better to know and get DS the help that he needs. I'll pray that he's just a small kid with high metabolism, but you definitely want to get things checked out. If there does turn out to be a problem, and you want to talk to a mom who's been there, feel free to PM me. GL!