We have purchased the Chicco Keyfit 30 which will hold baby until she's 30 inches tall OR 30 lbs in weight. Any second time + moms have any feedback on what age your child was when he/she reached 30 inches or 30 pounds? We're registering for a couple of convertible car seats but the one we're looking at doesn't have the option to be rear facing, so I'm curious how old baby might be when she reaches 30 inches or 30 pounds.