Maci Bookout is now the proud mother of a "beautiful" girl, and the MTV cast member is understandably cherishing this very special time with her longtime beau Taylor McKinney, her precious firstborn Bentley and her loved ones:

But before M and T welcomed Jayde Carter, the 23-year-old chronicled her second pregnancy during this season of "Teen Mom OG." From surprising Benny with his new older sibling title to settling into a dream home where they will make plenty of future memories, take a look back at these Baby JC-centric milestones in honor of her birth:

"We got a surprise"

T summed it up perfectly with the quote above when he and his girlfriend told the unassuming "TMOG" producers/crew that they would soon be welcoming a lil' guy or gal. Hugs and congrats ensued after the pair dished the deets, naturally.

Best big brother

Even though the six-year-old didn't quite believe that his mama was "having another," the darling kindergartner quickly understood his upcoming role -- and was soon grinning from ear-to-ear with excitement.

Ryan's reaction

A Teenage Mutant Ninja Turtle-clad Benny sweetly spilled to his dad about his sib on-the-way -- and M's ex nicely offered his heartfelt well wishes to J's parents.

Candid convo with Jen and Larry

M felt some butterflies discussing her baby-on-the-way with Ryan's folks, whom she also considers her second parents. But B's Mimi and Papa were very supportive and gushed that they couldn't wait for the brand-new addition to join the family fold.

Happy homeowners

Before Maci's mini-me made her triumphant debut, the couple found -- and moved into -- the perfect living situation for their expanding brood. Cheers to many more memories with their clan, under this roof!

+ Offer your best wishes to M, T, B and J below -- and be sure to catch part 1 of the "TMOG" reunion tonight at 10/9c!