Carlie McMaster was looking for more information on her father's side of the family when she submitted her DNA in 2019 to Ancestry.com.
The longtime Brantford, Ont., resident, whose dad had passed away a few years earlier, said while looking to learn more about her family's health history, the test to determine her genetic information linked her to the DNA of a woman in Minnesota named Rylee Hall.
After getting connected through Ancestry.com, Hall and McMaster began to chat in April 2019, including about how they might be related.
That's how McMaster learned they shared a biological father they had never met.
"I was definitely shocked, because I had no idea whatsoever, and really if I hadn't done Ancestry, I probably might not have known," said McMaster, 28.
Hall, 26, said she too was shocked, but had always sensed something was off — she felt she looked different than other members in her family, and suspected her dad might not be her biological father.
Hall's mother had told her she was conceived through a sperm donation a year before she connected with McMaster.
Hall said her mother had always planned to give her the news eventually, but the time never seemed right. She said her mother finally told her the truth after Hall told her she was planning to take an Ancestry.com test.
"It's not like everybody has to tell their kid they came from a sperm donor, so you can't really prepare yourself to do that," Hall said.
"I was happy that she told me, but maybe a little upset with the way she went about doing it and that she waited so long."
Hall said that when she reached out to McMaster, she didn't outright say they were half-sisters, because she wanted to be gentle about breaking the news.
McMaster said that once she and Hall came to the conclusion they were sisters, the Brantford resident pulled away because she thought Hall was pranking her.
"Now that I think about it, I was probably questioning my identity a little bit, but back then, it was more like, 'Push this unknown thing away. I don't want to deal with it,'" McMaster said.
Ten months after Hall and McMaster first made contact with each other, McMaster said she sat down with her mom and they finally talked about it.
McMaster said her mother told her she was conceived through sperm donation, and the father who raised her was not her biological dad.
McMaster quoted her mother as saying, "'It was very taboo back then, so we didn't know how to tell you.'"
While McMaster initially didn't know how to process the discovery, "Now I'm definitely happy about it because I have Rylee."
Both McMaster and Hall are in contact with Grant, a Toronto resident they never knew existed but who they learned is their biological father.
In the early 1990s, Grant was leaving Canadian Blood Services, where he was a regular platelet donor, when he noticed an advertisement.
"They had an ad for fertility donors in the elevator at the clinic," Grant told the CBC Hamilton in an interview. He signed up to donate sperm for the same reason he donated blood — because he wanted to help, he said. He didn't want his full name used for privacy reasons.
Grant said he donated twice a week for almost three years, excluding Christmas. Each donation produced around four vials, he said.
Grant, who is now in his late 50s, said he has tried to do the math and estimate how many people he could be genetically linked to through his sperm donation. He guesses it could be in the hundreds but the exact number is unclear.
Hall said her mother went through a full year of treatments before she became pregnant.
"Because my mom is older, she would go every single month to the clinic, and she did it 12 times ... once a month for a whole year, and on the 13th month is when they were like, 'Oh, it worked.'"
How Grant's sperm donation ended up in Minnesota isn't clear, but he theorizes it was because of his longevity and success as a donor.
"If you're a long enough donor, and you have successful pregnancies, they're going to have to change the geography," he said.
Grant said he was told that for every five successful pregnancies in a given geographical area, the sample would be moved. (Grant said the bank never specified the exact size of the area.)
Fertility clinics use this approach to keep from overpopulating an area with children who are genetically connected.
In the two years between McMaster's and Hall's birth, Grant said, the donations likely worked and had to be moved further west.
Grant said that when he donated in the 1990s, he had no idea that technology would advance enough that he could be found through online DNA tests. He said he had mostly forgotten about his time as a sperm donor as the decades passed, until a young woman, not McMaster or Hall, reached out to him.
Meeting the donor-conceived young women has been an eyeopening experience for Grant.
"For 30 years, you've just kind of wondered about it, and you know, all of a sudden you realize, 'Oh gosh, you have a child that's grown up. What does that child look like? What are their habitual things?' You know, nature versus nurture," he said.
From strangers to sisters
Once McMaster embraced she had a sister in the U.S., they grew close. At first, they shared long phone calls, and Hall said they still message each other a lot on every social media.
But their relationship deepened last fall, about a year after they first discovered each other, when Hall travelled to Ontario and stayed with McMaster in Brantford for 10 days.
"It just felt so normal once we were together," McMaster said.
"We have a lot of catching up to do," Hall said.
While in Ontario, Hall met McMaster's entire family and her friends. The two even got matching butterfly tattoos as a symbol of their sisterhood.
Hall plans to return to Ontario this August for an even bigger reunion.
Grant said that at the end of the summer, he, McMaster, Hall, and Grant's 17-year-old son will all meet and spend a weekend together in Toronto.
"They're just going to see what happens," he said.
3 other siblings
There's more in the McMaster-Hall story.
Through DNA websites, they've discovered other relatives.
"We've found three other siblings, so there's five of us, so far," McMaster said.
The other siblings are all women and were born in the mid-1990s in Canada. The three live in Western Canada, primarily British Columbia.
McMaster and Hall said that when they would find a potential sibling, they'd work together to draft a message that doesn't directly mention how they could be related, to see if the women already know.
"We don't want to freak anyone out or make them upset if they don't know," Hall said.
"I never want to ruin someone's life, obviously," McMaster said.
"Or the relationship they have with their parents," Hall added.
Podcast tells half-sisters' story
Since they've both had to tell their stories many times to different people, McMaster and Hall got the idea for a podcast that they're calling Our Daddy's a Donor.
The pair plan to retell their own story, and then branch out and discuss other stories of people conceived through sperm donations and who discovered the truth.
Grant said he's proud of McMaster and Hall for starting the podcast, because it might help others in similar situations.
"To hear somebody else's story makes us feel better because we don't feel alone," he said.
The podcast is set for release in August and will be available on Spotify and Apple Music.