Ashlee Simpson Says She's 'Proud' of Sister Jessica Simpson for Writing Revealing New Memoir

Ashlee Simpson is one proud sister!

On Sunday, the “Pieces of Me” singer, 25, shared a touching note to her big sister Jessica Simpson, praising the 39-year-old songstress on the publication of her revealing new memoir, Open Book.

Just over the weekend, Jessica’s book landed at No. 1 on the New York Times‘ best seller list.

“I am so very proud of my beautiful, brave, kind, loving sister!!!” wrote Ashlee, alongside a photo of the book’s cover. “It’s beautiful to see you sharing your truth with the world.”

“You are so inspiring. I love you so much,” Ashlee continued, noting Jessica’s NY Times accomplishment. “You are a No. 1 best selling author 😜.”

Jessica, for her part, responded to her sister’s words with affection.

“I could not have done any of this without your eternal love and endless support!!!” Jessica commented on Ashlee’s post. “Your bravery in life has taught me how to bandage up my wings and FLY 🦋 I love you 💚.”

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Later, Jessica posted an emotional message, thanking those for all of their support.

With her words came a black and white photo, snapped while Jessica was standing in a hallway and singing towards the sky.

“This is me singing ‘Hallelujah’ down the hall after finding out my truth not only set me free, but set the lives of so many readers and listeners of Open Book free… Meeting thousands and thousands of you these past 2 weeks has given purpose to my life all over again,” Jessica said. “My smile was real, my hugs were true, and these memories I will hold so close to my heart forever.”

“Thank y’all for helping my bravery break unexpected records and giving me the chance to be heard as a No. 1 BEST SELLING AUTHOR!!!” she said. “This is a moment for all of us to share, always and forever, your best friend…Jess 💚.”

RELATED: Jessica Simpson on First Love Nick Lachey: ‘We Got Crushed by the Media and by Ourselves’

Jessica Simpson | Kevin Mazur/Getty
Jessica Simpson | Kevin Mazur/Getty

RELATED: Jessica Simpson Reveals in Brave New Memoir: ‘I Was Killing Myself with All the Drinking and Pills’

Open Book, which Jessica penned with scribe with Kevin Carr O’Leary, finds the former Newlyweds star sharing her truth about some of her more personal behind-the-scenes struggles — from her body image issues and plastic surgery secrets, to how she felt about being compared to her pop-girl contemporaries and her relationships with exes like Nick Lachey and John Mayer.

One of her most vulnerable moments in the book? Jessica’s revelation that she was sexually abused as a young girl. The resulting emotional pain, along with other stressors, including career pressures, led her to self-medicate with alcohol and stimulants — a dependency that would later prompt her doctor to tell her her life was in danger.

“I was killing myself with all the drinking and pills,” she wrote.

Jessica got sober in November 2017 and hasn’t had a drink since. “Giving up the alcohol was easy,” she said. “I was mad at that bottle. At how it allowed me to stay complacent and numb.”

Therapy was the hard part, she went on to explain. As she wrote: “With work, I allowed myself to feel the traumas I’d been through.”

“Honesty is hard but it’s the most rewarding thing we have,” she said. “And getting to the other side of fear is beautiful.”

Open Book is on sale now.