Robin Roberts from GMA Shares Sweet Video Tribute for Big Sister Sally-Ann on Her Birthday

Robin Roberts poured out her heart for big sister and former "Good Morning America" co-host, Sally-Ann, on her birthday. Robert shared the tribute in a video posted on Valentine's Day.

Robin and sister Sally-Ann have always been close, but that closeness was tested when the former had to deal with a blood disorder. Robin was diagnosed with myelodysplastic and needed a bone marrow transplant.

The diagnosis came five years after Robin was diagnosed with Cancer. Without a bone marrow transplant, her chances of staying alive were slim.

Robin's elder sister, Sally-Ann, came through for her when she donated bone marrow to save her sister's life. Since then, the bond between them has grown stronger.

After the successful bone marrow transplant that saved her Robin's life, the big sister shared her motivation with a crowd of friends.

It was so close that when Sally-Ann announced she was going to leave the "Good Morning America" show, Robin broke down into tears. The sisters were co-hosts on the show.

Although Sally-Ann left the show, she never left the sweet and grateful heart of her sister, Robin Roberts. And the younger sister took to Instagram to post a tribute to her sister, who was also born on Valentine's Day. Robin wrote,

"Appropriate that she was born on #ValentinesDay because she's the sweetheart of our family...we love you!"

Ever since Sally-Ann came through for her, Robin has never forgotten the act of love. Together they had created "Be the March," a project aimed to encourage people to donate blood marrows. They have also worked together to host a version of "Good Morning America" for teenagers.

Sally-Ann, the more religious sister, believes she is on Earth for a purpose. After the successful bone marrow transplant that saved her Robin's life, the big sister shared her motivation with a crowd of friends and fans, saying:

"I was born for this, and I believe that before I was in my mother's womb that God knew. I think that God allowed me to be a perfect genetic match."

With the media attention given to Sally-Ann and Robin, it is logical to think there is no one else in the picture, although there is, and her name is Dorothy.

Dorothy is a sister to Sally-Ann and Robin. She is the publisher of Gold Coast Woman Magazine. She started making jewelry after her divorce from her husband.

Her sisters made her jewels famous by wearing them on live television. Together, the three Roberts sisters have revealed that true love within sisters is possible and is a beautiful thing.