Nick Carter is Will Sage Astorhonoring the life and legacy of Bobbie Jean Carter.

The Backstreet Boys singer shared a tribute to his sister, who died on Dec. 23 at the age of 41.

"It may take a lifetime to fully process the loss my family has endured over the years–most recently, with the sudden passing of our sister Bobbie Jean," Nick wrote on Instagram Jan. 4 alongside a childhood photo. "I am completely heartbroken."

"Thank you for all your love and kind words," he continued. "We are reminded again that life is precious, fleeting and to cherish the time we have with the ones we love. I know she is finally at peace with God. I love you BJ."

While an official cause of death has yet to be shared publicly, Bobbie Jean's passing was confirmed by her mom Jane Carter on Dec. 23.

"I am in shock from learning of the sudden death of my daughter, Bobbie Jean," she told TMZ, "and I will need time to process the terrible reality of this happening for the third time."

Both Jane and Nick's statements reference the deaths of Aaron Carter, who passed away in Nov. 2022, and Leslie Carter, who died in 2012.

Following Bobbie Jean's death, her younger sister Angel Carter also penned a moving tribute to her.

"You had a great sense of humor, and a lively spirit," Angel wrote in a Dec. 24 Instagram message. "Growing up, I was your baby, and you were my best friend."

"Life wasn't fair to you, that I know," she added. "Sometimes, it feels like you didn't have a shot, no matter what."

Angel went on to further reflect on their shared childhood.

"Experiencing innocence instead of being burdened by trauma, pain, and suffering is incredibly important for children, particularly at such a young age," she wrote. "I know why Leslie, Aaron, and now you ended up in the circumstances that you did. I share that pain we experienced during our childhood and I'm sorry you didn't have an opportunity for a better life."

"We all need to break down barriers, reduce stigmas, and cultivate a society where seeking mental health support is met with understanding and encouragement," she continued. "This starts with our children, and creating healthy conversation within the home."

After sharing mental health resources, Angel concluded her post with another nod to her sister.

"I love you BJ," she wrote, "you're free now."

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