Becky G has earned a pretty loyal fanbase, through both her upbeat Lantinx tunes and her role as film’s first gay superhero (AKA the yellow Power Ranger). But what those fans may not know is that the star has been keeping a family secret for years, and now she’s finally ready to reveal the truth.

“For the first time, I will be opening up about something that [my brothers] Frankie, Alex, [and sister] Stephanie and I, have lived with within our four walls, that I now feel ready in my heart to share with you guys, my extended family,” the “Mayores” singer told her fans via Twitter. She continued, “Today is my half sister’s 18th birthday. Yes I said it. My half sister.”

The 20-year-old went on to explain that she has a half-sibling who was kept a secret not only from the public, but also from other family members. “I learned about Amber when I was 13 years old,” she wrote. “When Frankie was old enough and ready, my parents and I also shared this with him. Soon after that, my parents, Frankie, and I spoke to Stephanie and Alex. We all had questions and dealt with the information in different ways, but most importantly, we handled it together — as a unit.”

While she didn’t go into any detail about how exactly Amber came to be a part of their family, she did say that the siblings were kept apart in the past “for reasons bigger than” them.

“We met for the first time this year,” she explained. “Her relations to the family in the past were always through my dad. At least up until recently. Although there has been effort on both sides to move forward in a positive direction, it takes time to catch up on 18 years and to process it all. It’s not something that happens overnight. It’s all been an emotional roller coaster. The history behind it all, is something that I’d like to keep private for the sake of Amber’s family and my own family’s privacy.”

However, she did want to talk more about the relationship she has — and hopes to develop — with her half-sister. “I had made a promise to myself that the day that Amber turned 18, was the day that I would reach out. As two individuals, legal, with no influence from either side, no baggage or bad blood from the past, in hopes that we can move forward in whatever direction us two decided to move in.”

She continued: “Now that she is 18, and her own person, so much in my life has changed and I now share my life with the world. But I’m sticking to my promise and I felt it in my heart to write this so that she knows.”

Have you ever had to deal with a surprising family secret? Let us know @BritandCo.

(Photo via Gustavo Caballero/Getty Images for AIDS Healthcare Foundation)