Friends have told how Heath Ledger was "desperately unhappy" in the final days of his life.
Ahead of the new documentary I Am Heath, the late actor's friends and family have talked about the private life of the famed actor, according to the Daily Mail.
Ledger was just 28 when he passed away from an accidental overdose in 2008 leaving behind a then two-year-old daughter, Matilda.
Towards the end, the star was struggling physically and emotionally, especially after his split with Matilda's mother Michelle Williams, those close to him said.
Ledger's sister Kate told People she one of the last people to speak to her brother before he died. She told the publication Ledger had a chest infection and she warned him to be careful with mixing medications.
"He said, 'Katie hello, come on, of course.' The night before he passed we were joking and laughing because he was threatening to take our little sister [Ashleigh] to get her nose pierced and then he said, 'I've got to go. I'll call you at 8.30 in the morning.' I told him 'I love you', and that was it."
Singer Mia Doi Todd said he threw himself into his last two roles and being away from his daughter was hurting him.
"I could sense the break-up with Michelle was driving him toward the edge. Not being the perfect father and the perfect partner to the mother of your child was really getting to him."
The actor had confided in his friend and vocal coach, Gerry Grennell, that he knew he had to stop relying on medications.
Grennell told People: "He missed his girl, he missed his family. He was desperately unhappy.
"He wasn't sleeping well and he was taking sleep medications, but they weren't working. He said 'I've got to stop.'"
Sadly, Heath did not stop, and on January 22, 2008, he was found dead in his New York apartment. He had suffered an accidental overdose.
Meanwhile, Matilda, according to Ledger's sister Kate, is the actor's greatest achievement and legacy - she is also a daily reminder of her late father.
Kate told People: "I still feel very connected to Heath. I feel connected to him through his beautiful daughter Matilda.
"When Heath was around, she looked so much like him, we used to say, 'It's Heath in pig tails.' Now everything she does, the way she rides a skateboard, reminds me of Heath."
Their similarities, at first, were a source of sadness, Kate said: "I think the first five years after Heath passed, every time I'd see Matilda [I] would be in tears.
"Now, I am really happy that I am at a stage that I can see Matilda and be happy and feel her daddy's energy through her."
While Kate sees Ledger in Matilda, she said she hopes the new documentary - set to premiere on Spike TV on May 17 - will help Matilda see herself in her father too.
She told People: "You can tell her about things, but with her being able to visually see his movement and his expressions, it's almost like he had actually filmed the documentary himself and pieced it together for her."
While he was not able to be a father for long, and he struggled with his own demons towards the end of his life, he was the best father he could be, longtime friend Matt Amato told the magazine.
"He was a natural, he knew what to do with a baby right away. I said, 'How come you are so comfortable with this?' He said, 'Well, I look at her and try and be her and try to understand what she needs.'
"I hope she remembers the way he would spin her around and call her darling and her excitement seeing him. They really did have something wonderful."
Ledger knew he would not live a long life, one friend revealed to the magazine, saying: "I don't feel like I have much time. I just don't think I'm going to be around that long. I don't know why. Just gotta get things done now."
This pushed him to live his life to the full, something the new documentary seeks to show.
Due to Ledger's passion for directing, most of I Am Heath is told from his own home videos.
In a trailer for the film shown on Good Morning America on Wednesday a never-seen-before video of Nicole Kidman played.
Kidman was one of dozens of stars who Ledger filmed in an attempt to capture their real lives and not just the ones they lived in the public eye.
Perhaps Ledger sought to do that as he struggled to ratify his private self with his public self.