Jenelle Evans' Instagram

Jenelle Evans' Daughter Is Already Smiling 'From Ear To Ear'

What's so funny, Baby Ensley?

Jenelle Evans is relishing and capturing one of the greatest moments of being a parent: having your munchkin grin back at you.

The Teen Mom 2 cast member -- who documented her third pregnancy during this season of the long-running series and welcomed her first daughter Ensley with fiancé David Eason at the end of January -- shared a heartwarming short video of her "sugar plum" cracking a priceless smirk.

"Smiling from ear to ear #MommasGirl #BabyEnsley #Precious," the mother of three captioned the clip above, which finds her mini-me looking a bit pensive at first and then flashing a happy expression. Nothing quite like seeing your infant jubilant and not crying (hey, the obvious needed to be stated).

Be sure to watch Jenelle reveal "100 Things About Teen Mom 2" throughout a Teen Mom 2 marathon today beginning at 2:30/1:30c -- and don't miss her and her loved ones during the Part 2 season finale of Teen Mom 2 tonight at 9/8c.