B.S.
My son was always 97th percentile weight and 80th percentile height until the age of 4, when things started evening out. He's now a solid 80/80 kid. Give them time to work through the baby stages (three still has the baby "fat" look!) and encourage her to be active and offer healthy snacks like carrots and fruits. You determine what she eats, she'll decide how much she eats.