Sean Lowe shared an adorable photo of his sons spending time with their newborn sister

The Lowe boys can’t seem to get enough of their baby sister.

Sean Lowe shared an adorable photo of his two sons with wife Catherine Giudici LoweIsaiah Hendrix, 19 months, and Samuel Thomas, 3 — staring at their newborn sister Mia Mejia on Instagram Thursday.

In the photo, Isaiah and Samuel wear white-patterned onesies that match the blanket wrapped around Mia as they crowd around her and smile.

“They love her. And like her daddy, she’s unsure about them,” Lowe, 36, joked in the caption.

Giudici Lowe announced the birth of their third child on Monday with a sweet Instagram selfie.

The proud mom of three shared a photograph of her children and herself on her hospital bed, writing, “Christmas this year didn’t have us unwrapping gifts under the tree or leaving milk and cookies out for Santa, but we wouldn’t have changed a thing. ?????.”

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Catherine Giudici Instagram
Sean and Catherine Giudici Lowe’s children
| Credit: Catherine Giudici Instagram

On Wednesday, Lowe also shared a photo of Samuel holding Mia in his lap.

“He’s a natural,” he wrote in the caption.

Lowe also announced Mia’s arrival with an Instagram post that showed him holding his baby girl in his arms. “I’ve always wanted a daddy’s girl and now I’ve got her. Mia is healthy, mama is doing great, and God is so good!” he wrote.

He added in a tweet, “We had a baby girl! Meet Mia Mejia Lowe (Mejia is Catherine’s family name). She’s perfect.”

RELATED VIDEO: Sean and Catherine Giudici Lowe Family Goals

The spouses met, fell in love and got engaged during Lowe’s season 17 of The Bachelor, tying the knot in a fairytale wedding that aired live on TV in January 2014.

They revealed their third pregnancy news exclusively to PEOPLE in June, with Giudici Lowe saying “it was a complete surprise” to be expecting again.

“Isaiah was 11 months old when we found out,” she added. “It was a little overwhelming to think about but we wanted a big family. This is just the way it was supposed to happen. So we’re excited.”

“Obviously, it’s going to be overwhelming and exhausting but they get to be best friends forever,” the then-expectant mom told PEOPLE. “We get to have these children who are going to be so close in age and get to grow up and have all these memories. Yeah, it’ll be hard for us but it’s just a chapter. It’s so fleeting.”

Later that month, the former reality star told PEOPLE she was hoping for a girl after two boys but would be happy either way. (The couple didn’t find out the baby’s sex before delivery day.)

“I had wanted to try for a girl and so that went through my head,” she said of the moments right after she and Lowe learned they were expecting again. “That went out the window! I thought, ‘Oh my gosh, I might have a third boy!’ And we won’t find out until it’s born. We’ve done that every time.”

“I definitely am praying very hard for a girl. I’m trying to think girl thoughts,” said Giudici Lowe, though she clarified that her baby’s sex is not what’s most important.

“That’s why we don’t want to find out. I’m going to love this baby no matter what,” she explained. “I’m going to find out when I meet it and love that baby.”