The results came back about eight weeks later. I clicked on the DNA Relatives section of the site, not thinking anything would come of it. But the first thing I read was, “Aaron Long: 50%. Father.”

“Bryce Gallo: 25%. Half-brother” was right behind.

Of course, I had known this might happen, but it hadn’t seemed likely. Before writing a note on the site, I searched for Aaron online to see what I could learn.

There are a lot of Aaron Longs in the world, so I set to work finding “the one.” I searched a professional social network for clues. Squinting at each Aaron Long, I wondered if I would recognise the donor right away.

One of the sperm vials listed the date of donation (1994), which helped narrow down birth and college graduation years. There was just one man with a master’s degree in literature in the correct age range, with the name Aaron Long. In his photo, he was wearing an olive-green silk turban and blowing a trombone. His profile said he was employed as a “communications specialist” and placed him in Seattle. A writer and a musician.

On another social media site, I discovered a Seattleite named Aaron Long with the correct workplace and with photos of each of his school portraits through the years.

There was no doubt. My daughters make that stupid face.

I quickly wrote a message to him on the DNA testing site. It read:

Hi Aaron, I actually have two daughters who’d match you (my ex has my youngest daughter; she’s not on the DNA testing site). If you’re interested in trading family photos, etc., we’re available.

I used the “curiosity hook,” thinking he’d have to write back to see pictures of my youngest daughter. Aaron wrote back immediately, sharing details I already knew from my sleuthing. He asked if I had any questions for him, and I asked if he was the shortest person in his family. I already knew the answer. He was.

We agreed to become friends on a social networking site and Aaron sent a 50-page long life history, which I devoured. He’d spent several years in a band in the town where we lived. How many times had we walked past him in the supermarket, I wondered?

I also wrote to Bryce, who had just graduated college. He told me he found Madi, a 19-year-old half-sister, and had also been in touch with other parents. He said there were a total of six children from Aaron, and that mine were #7 and #8. Bryce told me he had been raised with a little sister, but perhaps Madi, an only child, would be interested in developing a relationship with Alice?

Alice had to be cajoled into writing her life story for Aaron, and getting to know her DNA relatives is only mildly exciting for her. She is grieving the loss of her sister. I try to tell her she has a special job of guarding these people, getting to know them, and keeping them for her sister when she is able to meet them. However, she would rather have her sister.

A few months later, Bryce and Madi made plans to visit Aaron in Seattle. Alice was interested to see whether the siblings and Aaron resembled her. I agreed to let her take part.