Is it just us, or is Jason Aldean's baby boy, Memphis (nine months old at the start of next month) growing up too fast for words? His mother, Brittany, posted a cute photo on Instagram Wednesday (July 18) showing off his latest milestone: a brand-new smile featuring two freshly-cut bottom teeth.

"The cutest little chiclets I've ever seen," Mom says of the pearly whites, and Memphis himself certainly seems proud of his sparkling new grin. Many fans have commented on how Memphis uncannily favors his famous father in looks, and the new teeth are certainly helping that resemblance along.

While he's busy cutting teeth, Memphis will soon have to adjust to becoming a big brother. His parents revealed the big news this month that they are expecting their second child.

The couple just welcomed Memphis on Dec. 1, 2017, but they made no secret of the fact that they intended to have another child as soon as possible afterward. Aldean has two older daughters from his previous marriage, and both he and Brittany wanted to make sure Memphis had a sibling closer to his age to hang out with.

"Our theory is, 'Hey, we got one in diapers and formula right now so, while we're in this mindset we might as well knock it out,'" Aldean told Taste of Country Nights. "We both agreed that we wanted to have two."

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