P.S. from the Growing post. I just looked up the percentiles for Sierra and Maddie. Sierra is below the 5th percentile (she has always been this low) for height and weight while Maddie is in the 90th percentile for weight.
For those of you who don't know what the percentiles mean - Maddie being in the 90th percentile means that only 10% of babies her age are bigger than her - she is big for her age. That would mean Sierra is super small for her age - over 95% of kids her age are bigger.