Pete Wentz and his longtime-girlfriend Meagan Camper have announced the birth of their daughter, Marvel Jane Wentz.

In a post via Instagram, Wentz shared the news. The photo of his growing family was captioned, "So excited to introduce Marvel Jane Wentz. Feeling so grateful that she’s here... annnnd she’s already ready to takeover the world ❤️🌎 happy Mother’s Day @meagancamper and all the moms out there. We ❤️ you".

Marvel joins two brothers; 3-year-old Saint whose mother is also Meagan Camper, and 9-year-old Bronx (whose mother is Ashlee Simpson).

Wentz, who is the bassist for the rock band Fall Out Boy, was excited to have a girl around the house to combat all of the testosterone.

"I see my friends who have daughters, and it seems like a whole different kind of love that they have for each other, so I look forward to that being a completely new journey," he told PEOPLE. "Hopefully it'll bring some balance to our home!".

Wentz and Camper have been dating since 2011. They announced their pregnancy in January of this year on Instagram with a sweet photo of Brox and Saint. The two brothers are sitting with a pink box, wrapped with a pink ribbon. The photo was captioned, "Happy New Year! We’re kicking the year off with news of the best gift yet: 👧🏻 coming to our family in 2018... love Pete, Meagan, Bronx and Saint".

The couple's unusual choice for a name has been causing fans to wonder if perhaps she is named after the famous Marvel character - Captain Marvel. Marvel Studios is set to release Captain Marvel in March of 2019, as the newest addition to their Avengers series.

The film stars Captain Marvel, an Air Force pilot turned-superhero, who is played by actress Brie Larson. Her super-powers include, "flight, enhanced strength, durability and the ability to shoot concussive energy bursts from her hands".

It is not a stretch to think that these proud parents would want to bestow on their newborn daughter a powerful name that implies all of the feminine strength of Captain Marvel. Moreover, this name is unique and pairs beautifully with that of her brothers. Or perhaps the young family is just "filled with wonder and astonishment" at the arrival of their new baby girl, as the definition of the word suggests.

Congrats to the Wentz family on their newest arrival!

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