Lily Collins has a biographical book titled Unfiltered: No Shame, No Regrets, Just Me, in which she details the struggles of her past eating disorders, boyfriends and the strained relationship with her father Phil Collins.

Collins writes about how hard it was have to her father gone all the time as she was growing up, in a section of her book called "A Letter to All Dads."

"Because my dad was often gone, I never wanted to do anything that would make him stay away even longer,” she writes in the open letter in her book, released Tuesday, March 7. “I became extra careful about what I said and how I said it, afraid he’d think I was angry or didn’t love him. And the truth is, I was angry. I missed him and wanted him there.”

She writes that her parents divorced at the age of 5 and her father then moved from England to Switzerland for two decades, in which she rarely got to see him. The 26-year old actress also explained that she feels her father's absence is what triggered a lot of her struggles throughout her life.

"I’ve realized that many of my deepest insecurities stem from these issues with my dad,” the Golden Globe-nominated actress wrote. “It’s taken me over a decade to resolve some of them (others I’m still resolving) and to finally build up the courage to speak my mind to him.”

Collins goes on to say that her her "A Letter to All Dads" essay could be a guide for other young people, enduring hardships with their parents. The letter ends with forgiving her father for not being there and inviting him to get to know the person she has grown up to be.

“I forgive you for not always being there when I needed and for not being the dad I expected. I forgive the mistakes you made. There’s still so much time to move forward. And I want to. I’m inviting you to join me. I’ll always be your little girl," the letter concludes.