Aaron Carter's twin sister, Angel Carter-Conrad, has shared a new detail about the late pop singer's ordeal days before his untimely death. In her tribute to Aaron on what would have been his 35th birthday Wednesday, Angel revealed that she had pleaded with her brother to let her help him with what he was going through just two days before his death.

Sharing a photo of her and Aaron during their early years, Angel wrote, "I want to start by sharing how much I appreciate all the birthday wishes. While today is incredibly tough, I am overwhelmed by your love and support. Thank you from the bottom of my heart."

Angel reflected on the grief she felt when she lost their sister Leslie in 2012, saying the death of Aaron has compelled her to deal with the same pain again. "Almost 11 years ago, I lost my sister Leslie," she wrote. "I remember feeling broken, confused, and I questioned how I was going to continue on without her in my life."

"And now, over a decade later, I am forced to once again deal with the extreme grief of the death of a sibling. This time, it's my beloved twin, Aaron. We had an indescribable bond... and now, he is gone," she continued.

Angel said the difference between her siblings' deaths was that with Leslie, she was "blindsided and shocked." With Aaron's death, however, she said their family had tried everything to help him with his untreated mental illness and addiction days before he died.

"I spoke with him two days before he passed, and I begged, once again, for him to let us help," she wrote, adding that she did not know that would be the last time she would ever hear his voice.

"Aaron dying was the worst day of my life. I have loved him since we were born... It feels like a piece of my soul is gone. And yet, despite all this pain his passing has lit a fire within me. I feel a calling and responsibility to help other families and continue the conversation to further break the stigmas that surround mental illness," the 35-year-old wrote.

Angel also announced plans to stage a benefit concert to raise awareness about mental health in January 2023, the proceeds of which would be donated to the On Our Sleeves organization. "I have learned the pain never goes away and keep telling myself that it is one step at a time. I am hoping you can join me for this crucial next step... in memory of Aaron," she wrote.

Aaron died at his home in Lancaster, California last Nov. 5.

Aaron Carter
Aaron Carter attends 102.7 KIIS FM's 2017 Wango Tango at StubHub Center in Carson, California, May 13, 2017. Getty Images/ Frazer Harrison