Inside the late wife of Richard Branson's incredibly close bond with children Holly and Sam

Richard and Joan were together for almost 50 years before her passing, and shared kids Holly and Sam, as well as their eldest child, Sarah Clare, who was born three months premature and died four days after her birth due to complications.

Joan was incredibly close with her children and her five grandchildren, including Etta, Artie, Lola, Eva-Deia and Bluey Rafe.

Holly, 44, opened up in July about how Joan didn't blink an eye when she decided that she identified as a boy in childhood, and supported her decision every step of the way. "The last few weeks have been filled with so much love and magical family moments," Holly began in a social media post celebrating Joan's 80th birthday.

"As a family, we love to be surrounded by people (strangers and friends alike), great food, good music, bad dancing, and lots of laughter. My heart is full after an early celebration of Sam's 40th birthday onboard...quickly followed by [my] wonderful mom's 80th birthday."

"My mom hates to be in the spotlight, but I'd love to share some of the most precious lessons I've learnt from her," she continued. "The most amazing quality my mom has is the ability to love unconditionally... Having a daughter who decided from the age of four that she wanted to be a boy must have been difficult to navigate back then."

"Mom (and Dad) never made me feel like I was strange in any way, and I am so thankful to them both for this," she added. "Mom has always been so open-minded, empathetic and kind."

"Truly letting me and Sam be totally free to become the people we wanted to be...I've realized that unconditional love and support also comes with a large helping of patience, thank you for teaching me that, Mom."

Joan also shared a close bond with her son, Sam, 40, who shared a heartbreaking tribute to his mom after her death was announced. "Mom, you instantly made everyone in your presence feel like all was well with the world. You were the kindest, most loving, warm and abundantly generous woman to walk this Earth," he wrote on Instagram.

"Thank you for all that you were to me, our family and to everyone who was blessed by your graceful, loving presence. I am so deeply grateful to have had the privilege of being your son and being able to call you mom."

"Words cannot express how much I will miss you and how I wish you were still here to console me about the loss of you. But somehow you still are…and that is the magic of you. I love you to the moon and back. Forever and Ever."

Richard and Joan rarely spoke about the loss of their eldest child until the Virgin Group founder shared insight into how welcoming Holly and Sam allowed them to find joy again.

"I don't think anything could have brought us closer together, and I don't think we needed to go through something like that to bring us closer together," Richard explained on Piers Morgan's Life Stories. "Having Holly and Sam, you know, 100% bound our relationship forever."

"We've been absolutely blessed [to have] two fantastic kids. There are other people we know who've lost a child who weren't able to carry on and have other children. For them, that's a nightmare they have to live with for the rest of their lives. For us, we just got two of the best kids we could imagine."

Joan largely remained out of the spotlight throughout her life and supported several premature birth charities in honor of their late daughter, Sarah Clare.