Adopted woman searches for biological siblings and learns there are 13 of them

"I thought I was the only child."

Shaquanna Bell, 33, found out in middle school that she had been adopted.

"I was shocked," Bell, a chef from Houston, Texas, told "Good Morning America" of her adoption. "I had no idea. I had a fantastic life growing up. It raised questions but I didn't really pursue it because I was 13 years old and I just went on with my life. I [thought], 'OK, well, I must've been adopted for a reason.'"

Later, Bell's parents showed her the adoption papers and her birth certificate, which revealed she was born in New York. Bell also learned her biological mother's name: Equilla Haines. Haines died in 1998 from cancer.

Bell said since she has no social media accounts, her niece, Jaquelyn Collier, offered to help her track down any family members she may have in the world.

One woman found by Collier had the name Equilla Haines, which was the same as Bell's biological mother. Collier confirmed that Equilla Haines was Bell's biological sister.

It was soon revealed that Equilla Haines wasn't the only one. In total, Bell had 13 biological siblings. Add that to her eight adopted siblings for a total of 21.

"I was like, 'You're kidding,'" Bell recalled. "I didn't think she was serious. I felt overwhelmed and nervous because I thought I was the only child."

Bell said she was her birth mother's 10th child. Her siblings are: Janell Haines, 51, Equilla Haines, 49, Keith Tabb, 48, Sha-ron Tabb, 46, Alisha Wyche, 44, Eboni Veba, 43, Loretta Grant, 39, Tawana Grant, 37, Quantavia Grant, 35, Shaquanna Bell, 33, Crystal Bailey-Haines, 31, Elyse Lane, 29, Shaynyse Lane, 29 and Levell Lane, 27.

Bell said she has video chatted and spoken with all of her brothers and sisters except one.

Janell Haines, the eldest sibling of the group, said she's always known she had another sister in the world but had no idea where to look.

Haines said she and four of her siblings lived with their mother. Others were in foster care or were adopted.

"My mother was an active drug user," Haines of Springfield, Massachusetts, told "GMA." "I've been on my own since I was 15. We've just been all over the place."

Haines said her mother was very open with her about the fact that she had siblings in the world whom she didn't know. As the years progressed, many of them reached out to Haines on Facebook, revealing that they were siblings of hers.

"It was MySpace first, that's how my sisters Alisha and Eboni found us," Haines said, adding that she met her sister, Crystal Bailey-Haines, two years ago.

Two weeks ago, Haines' son told her that Bell, the final sibling she never knew, had found them.

"I felt complete," Haines said, crying. "She's been the missing piece to our puzzle. I've never got an opportunity to hold her in my arms. I didn't think we were ever going to find her. We've all never been in one space together."

She went on, "I will kiss [Bell's] whole face, tell her how much I love her and how I've missed her."

Bell said she hopes to raise funds so she and all her siblings can finally meet in person.

"It's going to be very emotional," Bell added.