18-Year-Old Searches For His Sperm Donor And Finds Out He’s The Youngest Of 40 Siblings

A college student simply searching for information about his sperm donor ended up getting more than he was prepared for. Ben Sanderson knew that he had been conceived using a sperm donor. At 18 years old, his mom told him he could begin searching for his biological father and any possible siblings, if he desired.

In 2023, the Indiana University college student's curiosity was piqued and he began his search. What he wasn't prepared to discover was that he has 40 siblings — and he's the youngest of them!

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With the help of his mother, Ben logged into the sperm bank's website to access its sibling registry and chat room where those from the same donor are able to leave messages to connect with one another.

When he did that, Ben discovered a message from a half sibling of his sent 11 years ago. "It basically said, 'Hi, my name is [name], and I'm your half-sister…'" he exclusively told People.

Reaching back out, Ben sent her his Instagram handle and wrote, "Hi, my name is Ben. I’m a donor child with the same donor number as you. I’m 18 years old and just logged onto the sibling registry for the first time today. I saw your message and would love to connect. Please let me know if you see this."

To his surprise, she sent him a direct message on Instagram the next day saying she'd love to get to know him. They began talking, and after a while Ben noticed he had a lot of new followers that were mutual friends of hers. He soon realized that many of them resembled him, and would turn out to be his siblings, too.

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Another sister reached out to Ben via Instagram, and offered to add him to a group containing 15 of the siblings. "I was told I would only have a maximum of 10 siblings," he recalled. But the sister had news for him in her reply.

"No, there are 40 of us!" she said. "I was in a restaurant when I found out and realized that I was the youngest of them all," the college student said. "It was the best day ever. I was so excited. I was like, 'Get out of here!' That’s the best fun fact ever. No more saying I'm double-jointed."

Since finding them, Ben has taken the time to learn all about his siblings. He's been able to gain a ton of information about them through a spreadsheet they created, including things like their zodiac signs, college majors, if they're vegetarian, and the age they discovered they were donor-conceived.

While many of them are close, some of them don't desire getting to know each other. "I have a lot of siblings that I've never talked to because they don’t want a relationship," Ben explained. "Especially with the rise of 23andMe and Ancestry, straight parents who lied to their kids about being donor-conceived are now finding out."

Ben has also found and connected with his sperm donor, whom he refers to as his dad. "He was thrilled to learn that I’m an actor," the student said. "He used the sun and the moon as metaphors for our relationship, saying that even though we’re far apart, it’s still an important connection in the galaxy. He essentially wanted to match the energy I was giving him." They've continued to keep in touch since.

In hindsight, Ben says he's glad that he waited until he was 18 to begin his search. "My mom and I were on the same page about this," he said. "I was an adult when I found them, so I could make my own decisions and set my own boundaries. I had 18 years of knowing that I wanted to find them. I think trying to search as a child would have been overwhelming."

Ben also believes he's at an advantage for finding out about his siblings later on. "I think the advantage I had over my siblings is that the 40 of them found each other before I did," he said. "One of my sisters mentioned that she only knew of seven siblings at first, then 12, then 17. She would wake up every day wondering, 'Am I going to get another sibling today?'"

While he continues to create relationships with his siblings, Ben remains open to the possibility that there may be more of them out there who may pop up one day. "I’d be really upset if someone younger than me shows up and I’m no longer the baby of the group," he joked. "If they’re older, that’s fine. But if they’re younger, I’m going to be so sassy about it. I want to be the youngest!"