Brief update -
Aria had her four month well child check up
She now is 26" long (which is in the 98th percentile)
weighs 14 lbs 3.0 oz (6.435 kg) (66th percentile)
and her head circumference is 41.5 cm (43rd percentile)
and her doctor gives her a perfect bill of health.
She is laughing and reaching and smiling all the time. She can lift up her whole upper body on her tummy and can accurately get toys into her mouth. She still loves to gnaw on her fingers and is a drolling fool. She clearly admires her older brother and sister watching all they do and responding easily to their coos.