Hayden Panettiere Was 'Heartbroken' After Giving Up Custody of Daughter Kaya, Claims Source: 'Always a Sadness There'

Hayden Panettiere's decision to give up custody of her daughter, Kaya, was proof that she only "wanted what was best" for her, a source claimed after the actress' sudden death earlier this week.

"It takes a certain kind of strength as a mother to recognize that what you want for yourself may not be what’s best for your child," a source told People on Monday, August 17. "Of course Hayden wanted to be with Kaya every day, but she also knew that she was struggling and that Kaya had stability with her dad and family. As painful as that was for Hayden, she put Kaya first."

As OK! previously reported, the Nashville actress died at 36 on Sunday, August 16, after being found unresponsive in a South Carolina apartment complex following a suspected overdose.

She left behind her 11-year-old daughter, whom she shares with her ex-fiancé Wladimir Klitschko.

"Hayden struggled for a very long time, and she wanted nothing more than to get better and stay sober," the insider told the outlet. "It was just incredibly difficult for her. But even when she was struggling, she wanted what was best for Kaya."

Though the Heroes star was devastated when the professional boxer, 50, asked for full custody of their daughter, she didn't challenge the request and voluntarily signed over her rights.

"She was so incredibly proud of Kaya. She’d talk about her all the time, and you could see how much she loved her. But there was also always sadness there," the source continued. "It was heartbreaking for Hayden that she wasn’t able to be part of her daughter’s everyday life."

The source continued, "She knew that her daughter was safe, loved and being taken care of. That gave her comfort."

The Ice Princess star spoke at length about the guilt she felt from the decision in her tell-all memoir, This Is Me: The Reckoning, which hit bookshelves in May.

"I grieve that I’m not the mother I want to be (trust me, no one should ever have to raise a child on FaceTime) and although I miss Kaya so much my heart aches, I know how blessed I am to be her mom," she wrote in her memoir. "She is the greatest gift of my life, with all the best parts of her father and me."

While promoting the memoir, Panettiere responded to a question about what she hoped her daughter would one day understand from reading the book.

"I don't want her ever to read it and think any of it was her fault. I love her so dearly. [It’s a lot for an] 11-year-old to process that," she said at an event in Los Angeles, Calif. "I’ll continue protecting her, especially while she’s young."