Nick Carter paid tribute Sunday to his younger brother, Aaron Carter, who was found dead at his Lancaster home on Saturday. The singer, rapper and sibling of Backstreet Boys vocalist Nick Carter was 34.

On Instagram, Nick Carter shared a series of photos from his childhood with Aaron Carter. In the pictures, the brothers can be seen walking arm-in-arm through the woods, enjoying a family boat ride, sharing some hugs and smiling at the beach.

"My heart is broken," Nick Carter captioned the post. "Even though my brother and I have had a complicated relationship, my love for him has never ever faded. I have always held on to the hope that he would somehow, someday want to walk a healthy path and eventually find the help that he so desperately needed."

The Los Angeles County Sheriff's Department said Saturday that authorities were investigating the circumstances surrounding Aaron Carter's death after receiving a call from a house sitter who found him unresponsive in a bathtub.

Following in his pop-star brother's footsteps, Aaron Carter began recording and releasing music at just 9 years old. In the late 1990s, he dropped his eponymous debut album and opened for the Backstreet Boys on tour. His early hits included Aaron's Party (Come Get It), Crazy Little Party Girl, I Want Candy and That's How I Beat Shaq.