Benjamin Keough would have celebrated his 28th birthday on Tuesday, Oct. 21.

The young man, son of Lisa Marie Presley and Danny Keough, tragically died on July 12. He was just 27 years old. Devastated by the ineffable loss, Benjamin's family marked what would've been his birthday with tributes on Wednesday.

Lisa Marie Presley's tribute to late son Benjamin on his birthday

Lisa Marie Presley, the only child of Elvis Presley, penned a heartbreaking tribute to Benjamin on her Instagram page. "My beautiful beautiful angel, I worshipped the ground you walked on, on this earth and now in Heaven," she wrote.

"My heart and soul went with you. The depth of the pain is suffocating and bottomless without you every moment of every day. I will never be the same.

"Please wait for me my love, and hold my hand while I stay to continue to protect and raise your little sisters and to be here for Riley. I know you would want that. Happy Birthday my sweet sweet Boy. You were much too good for this world," the tribute concluded.

Benjamin was survived by sister Riley Keough and two half-sisters, twins born to Lisa Marie Presley and Michael Lockwood—her fourth husband and now ex.

Riley Keough remembers late brother Benjamin

Keough, 31, kept it short but sweet in her birthday message to her late brother. "Happy Birthday beautiful angel," she wrote, with cloud and heart emojis, and pictures from throughout their lives together.

Just over three months have passed since Benjamin's tragic death on July 12. Days later, it was ruled that he died by suicide. He was the only son of Lisa Marie Presley and the only grandson of Elvis and Priscilla Presley.

Elvis Presley

Quiz

In what year did Elvis Presley pass away?