Amber Portwood couldn’t contain her pride when her OB-GYN told her she was carrying a “stubborn” little boy.

The Teen Mom OG star went in for an ultrasound with her boyfriend Andrew Glennon and her mother Tonya Portwood on Monday night’s episode of the MTV show.

“Is your little girl excited about having a baby?” her doctor asked while attempting to get a good view of the fetus.

“Yeah, she said she wanted a little baby brother,” Portwood, 27, said of her daughter Leah, who she shares with ex-boyfriend Gary Shirley.

After several moments of trying to see whether she was carrying a boy or a girl, Portwood was asked to bend her knee in an attempt to shift her baby into a better position to find out the sex.

It seemed to work as her doctor declared, “That is for sure a boy.”

The reactions were immediate as Portwood gasped and clapped her hands, while Glennon wiped tears from his eyes.

“That is a boy, a very little stubborn baby boy. Super stubborn,” the doctor continued, referring to the multiple attempts of shifting the baby in position to get a clear view of the sex.

Glennon said, “ gets it from his mom. I have three sisters so I thought it would be a girl for some reason. But this is great, this is fantastic.”

Portwood decided to surprise her daughter with the news at her 9th birthday party.

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“Booboo, I have something to tell you,” she said. “I know what I’m having. I’m having a boy. So you’re going to have a little brother, your first little brother.”

Leah gave her mother an enthusiastic, “Yay!” before continuing to enjoy the party with her friends.

After the party, Shirley spoke with his wife Kristina about Leah’s reaction to the news.

“She’s always said… like that was on her Christmas list, she wanted a baby brother but she put it like from us,” Kristina said. “I’m like, you’re not going to get baby from us. She hasn’t spent a lot of time with her mom since she’s been pregnant.”

Shirley added, “She’s getting used to Andrew too. A lot of changes. Leah, she went through a lot because, Matt is out of the picture, her buddy, who she did a lot with. Then her mom wasn’t coming around. Then Andrew comes into the picture, three weeks later she’s pregnant. It’s like a lot to take in for her. It’s quite a bit.”

Recently, Portwood shared a photo of herself, Glennon and Leah on Instagram with the caption, “Love my little family.”

Teen Mom OG airs Mondays (9 p.m. ET) on MTV.