“I’m sorry I couldn’t save you. Love you, oh how my heart misses you,” she wrote.

Liam Payne‘s sister Ruth Gibbins is breaking her silence following the singer’s death.

On Saturday (Oct. 19), Gibbins shared a heartbreaking tribute to her brother three days after he passed away at the age of 31.

“I don’t believe this is happening. Many times I have poured my heart out publicly with pride about Liam but never much about life as his sister,” Gibbins began her lengthy statement on Instagram. “Liam is my best friend, [no one] could ever make me laugh as much as him, doing his impressions always had me creasing and he loved seeing how much of a laugh he could get.”

The grieving sister went on to explain that Payne “moved out when he was 17 to chase his dreams” and that she would visit him during his stint on The X Factor, the U.K. talent show he appeared on before hitting it big with One Direction.

“I would regularly drive to have tea with him after I finished work, just to sit around,” she wrote. “One month the hotel was right by a wagamamas and I swear he had it morning, noon and night!”

Gibbins added that “Liam loved 1D” and referred to the group’s Harry Styles, Zayn Malik, Louis Tomlinson and Niall Horan as his “brothers.” She also noted that Payne “knew he could call me anytime” and that she would often help her sibling work through his issues.

“Liam, My brain is struggling to catch up with what’s happening and I don’t understand where you’ve gone,” she continued, addressing her brother directly. “I just want to drive to your house and walk in to music blasting and find you sat there writing a song.”

Gibbins added that Liam possessed a great “kindness” and had the “ability to make me laugh.” She also noted “how proud I am to call you my brother and my best friend.”

“I don’t feel this world was good enough or kind enough to you, and quite often over the last few years, you’ve had to really try hard to overcome all that was being aimed at you,” she wrote. “You just wanted to be loved and to make people happy with your music. You never believed you were good enough, I hope you can now see this outpouring of love that you never received in your time.”

She concluded her post, “I’m sorry I couldn’t save you. Love you, oh how my heart misses you, Ru xxx. One last thing I need to know, I’m here if you need anything, I’d drive to the end of the universe to bring you back.”

Gibbins’ emotional post was accompanied by numerous photos, including a snapshot of the brother and sister on her wedding day and other pics of the pair spending time together.

The former One Direction star died on Wednesday (Oct. 16) after suffering a fatal fall from the third floor of his hotel in Buenos Aires, Argentina. Investigators believe that he was potentially under the influence of substances when he fell, but they are still waiting for further toxicology reports.

See Gibbins’ tribute to Payne on Instagram below.