Pediasure

So we had a well baby visit today. She weighs 21 pounds 4 ounces (between 10 and 25 percent) and is 31 inches tall (50 percent). The doc was not worried but said that I should give her some pediasure...
I am pretty sure I read about someone else's little one drinking pediasure, but I don't remember who.
I am not sure if she will drink it. But she has been at the same percentiles the whole way so I am not that worried about it now. And she did get taller, so that makes me feel better as well.

Worried about weight

So I finally compared her numbers from her last dr visit to this past one. She went from 21 pounds 6 ounces at 13 mo to 21 pounds 4 ounces at 16 mo. She also seems to still be around 28/29 inches tall. We have a regular well-baby appointment on Monday and I am going to ask. But should I be worried?
I know that she is running all over the place right now. And she is still nursing 4-6 times a day and eating some solids.