Nick Carter has claimed his family blamed him for the death if his younger sister Leslie.
Leslie died last year after taking an apparently accidental overdose of prescription drugs and the Backstreet Boy opened up to US TV psychologist Dr Phil about her death, admitting he blamed himself.
Nick, 33, said: "There's definitely a part of me that did blame myself... It was tough. You have to find a way to move on as well as take care of your family at the same time."
The singer - who has just published his memoir Facing The Music And Living To Talk About It - battled drink and drugs, and as part of his rehabilitation had cut himself off from Leslie in the months leading up to her death. This led to his family blaming him, he claimed.
Nick fought back the tears as he revealed: "I thought that was unfair. There comes a point where you have to ask yourself if you're hurting them or helping them."
Nick did not attend Leslie's funeral. " The reason I did not go... I started to get blamed by the rest of the family for her death.
"It has been toxic. The communication is something I'm still trying to work on by going to therapy."
Nick, who grew up the eldest of five siblings, spoke about his difficult childhood.
He revealed: "It was just the way my household was with my father: he was a dominating personality. He led by fear... I believe you should lead with love.
"I always had a lot of pressure when it came to my siblings. I became the father... I was making more money that my father did at the age of 14 or 15. I became the provider."