She. Has. ARRIVED!

On Saturday, August 28, Catelynn Lowell and Tyler Baltierra announced the blessed news that their immediate family has expanded once again.

The beloved couple, who have starred for years together on Teen Mom OG, just welcomed baby number-four, a precious little girl whose name remains unknown at this time.

“She’s here and she’s perfect,” Baltierra captioned an Instagram Story video of the newborn’s bassinet in the hospital this morning... adding emojis of a crying face, heart eyes and a red rose.

He did so just a few hours after his wife told the world that she was iin labor.

"Baby R is on her way," wrote Catelynn late Friday. "send positive vibes."

Catelynn and Tyler when made their small screen debuts on 16 and Pregnant back in 2009.

Sweethearts since high school, the spouses at the time were considering whether or not to give daughter Carly up for adoption.

They decided to do so in the end, with Catelynn and Tyler remaining in pretty close touch with the now-11-year old's parents, who even appeared last year on an episode of Teen Mom OG.

The pair are also parents to daughters Novalee, 6, and Vaeda, 2.

Their new arrival this weekend comes after Catelynn shared devastation in December 2020 that she had experienced a pregnancy loss.

As for why she wanted to share it with fans, the MTV star said she realized other parents had experienced similar situations -- and she wanted to serve as a kind of role model.

"I opened up about this only to help those who are experiencing the same thing to know that there's someone else every day experiencing this," Catelynn wrote on social media.

"This was painful to share... but again, you're not alone."

The Teen Mom OG stars revealed then their pregnancy news in February, noting that their “rainbow [baby] was worth the storm.”

Lowell posted a photo earlier thos year of Novalee and Vaeda wearing “big sister” shirts, writing as confirmation:

“Baby Baltierra coming soon.”

The Michigan native also uploaded snapshots of her ultrasound and her positive pregnancy test.

“We have found out that we are going to be having a … drumroll please … another girl!” the MTV personalities later said.

“While we wanted a boy since this is our last, as long as she’s healthy though that’s really all that matters.

"This is our last and final, but we know one day we will have a grandson and adore him!”

Viewers have watched Catelynn and Tyler go through pretty much everything as a couple:

The former once entered rehab due to postpartum depression, while the spouses even tried out a separation in 2019 -- although they made it clear at the time that divorce was neever an option.

"When it comes to mental health stuff, miscarriage stuff, I feel like I'm always open and honest about it even if it's hard to do it just because it makes people realize that they are not alone and somebody else has gone through it," Catelynn told E! News in January," adding:

"I can help people realize they're not alone and then I can realize I'm not alone too."

Just last month, meanwhile, Tyler and Catelynn celebrated their 15th anniversary as a couple.

Wrote Tyler in tribute/celebration:

I love those dreamy eyes/Staying up talking late at night/Snuggle close right by my side/Hair tickling my nose, I don’t mind/Go ahead, lay down your head/Feel my heartbeat in your hand/Just let me hold you until the night ends.

15 years together & you still make me feel as if we were goofy kids! I love you so much babe @catelynnmtv.

All that, plus the guy is hung AF!

Teen Mom OG returns Tuesday, September 7 at 8 p.m. on MTV.

Congrats to the happy family!!!!!!!!!!!!!!!