We weighed the kittens again and Agnes is a full 7lbs! That's about 1.5lbs she's added in a little over a months. Other than the big post-meal belly, she is a clean, lean, kitten machine.
She has added even more phrases to her vocabulary. I'd even venture to say that she's talkative. Most recently, she started to sing out and add a playful "brrrr" sound on the end when she wants attention. This new song is generally followed by a paw tap on the leg, requesting she be picked up, or prior to her presenting her belly and the 'air biscuits' she hasn't quite mastered.

Sir Henry, seen here getting his gentleman on, now weighs 6.4lbs. He's been a little behind his sister in growth and teeth development, but he has more energy to burn and is a more lanky. He doesn't engage in the 'MEOW' unless it's during the shark frenzy that occurs while their food is being transferred from can to bowl, but he narrates almost all of his actions with chirps and grunts. I am curious if the other Pettibone kittens have similar vocal tendencies.