Today's the day! Teen Mom OG stars Catelynn Lowell and Tyler Baltierra will finally get to reunite with their firstborn daughter Carly — who they placed for adoption back in 2009 — after two years of being apart. Tyler took to Twitter on Friday, Aug. 18 to share some insight into their relationship with her adoptive parents and he couldn't contain his excitement about what is sure to be an emotional day.

"On the plane to go see Carly for the first time in [two] years. Can't wait to see her [and] Novalee together. Warms my heart just thinking about it," the 25-year-old wrote, confirming that his second daughter — whom he shares with Catelynn — is also joining them for the reunion with her birth sister.

Fans started asking Ty about the rules that Carly's parents — Brandon and Teresa Davis — had set in place. The couple previously asked Catelynn and Tyler to refrain from revealing too much information about them on Teen Mom OG, and they also asked them not to post any recent photos of Carly in order to protect her privacy, but Ty explained what he can and cannot do when it comes to Carly.

"I can talk about whatever I want. The rule is not to post PICTURES [sic] of her on social media," he wrote. He also explained that Novalee does know that Carly is her birth sister, and he mentioned that he does respect Brandon and Teresa's wishes because they are Carly's parents since they raised her since she was born.

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Fans also asked Tyler if Carly would be able to choose to have more of a relationship with him and Catelynn once she turns 18 years old. "She will be allowed to do whatever [Brandon and Teresa] allow her to do," he wrote, and he even said that there could be a possibility that Carly would choose to not have a relationship with them at all. "[To be honest] it would hurt, BUT [sic] she would never know it hurts, because she deserves to make that decision herself, guilt free," he wrote.

Earlier this year, Tyler posted a throwback photo of when Nova, 2, met her sister for the first time. He captioned the sweet snap, "Throwback to when Nova met her birth sister Carly for the very first time!" and used the hashtag "#MyGirls" with a heart emoji. Adorable!

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The parents, both 25, opted for an open adoption, meaning the biological and adoptive families have access to each other's personal information and have the option to contact one another and even meet face-to-face. However, Catelynn and Tyler don't get to see Carly often. The now-eight-year-old (yes, eight) was adopted by Brandon and Teresa, and we witnessed the reality stars getting frustrated on the show because they were denied visits, most recently last year. Cate said, "Are we done having visits with Carly forever? Until she’s 18 I’ll hear nothing from her? It is f–king frustrating because I was 16 years old when I made this decision."

Yet Tyler admitted that Brandon and Teresa have the right to not let her see them. "They will always be justified because they are her parents and we are not,” he tweeted in October 2016. “We do have an open adoption. They are just making decisions that they think are the best for Carly. Which is exactly what they should do."

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Luckily, fans should be happy to know that the two aren't finished having kids just yet! In an interview with People in April, Catelynn said,"To all the people who are freaking out because they want me and Tyler to have more babies, we will one day… I’m definitely still on birth control." We'll be patiently waiting for another little Baltierra!

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Scroll through the gallery below for photos of Tyler and Cate's cutest moments!