The donor-conceived siblings connecting across the world
Iori, Sam and Jack live in different parts of the world - but all share the same donor father. Now, their parents are helping them to connect.
On a laptop on a kitchen table in Chiswick, west London, two brothers are trying to Skype another brother in Canada.
As the line connects, a single mum, or "mom", from Ontario called Magen waves back at the camera. She holds her one-year-old son, Jack, aloft so he can be seen.
"Look Jack, there's your brothers over there," she says from her sitting room 3,000 miles (5,000km) away, pointing to two-year-old Iori from the UK and 11-month-old Sam, whose parents have brought him all the way from Seattle in the United States to meet his donor sibling.
The three children, who surnames we are not using, are connected because their mothers used the same sperm donor from a clinic called Xytex in the United States, although none has met their biological father.
Because the children are so small, for now, the contact is really being driven by their parents.
But this particular network of donor-conceived siblings - or "diblings", as they're also known - doesn't stop at three children. To date, there are 12 of them, living across the world.
Only Iori lives in the UK. His mum, Maxine, a BBC journalist, says she had suspicions her son would have half brothers and sisters when he was born.
"I remember when I'd just had him and I was sitting in hospital thinking, 'He's probably got siblings and that's really sad because he doesn't know them and he won't know them.'
"I grew up with siblings and I thought if that was me I'd really want to know," she added.
The notion of a traditional family, consisting of a mother, father and 2.4 children is constantly being challenged. Developments in fertility treatment and a shift in social attitudes over the years have helped couples have children who previously might not have been able to, including through donors.
In the UK, a donor-conceived child is not allowed to know the identity of that donor until they are aged 18.
It is the same in the US, but tracing a half sibling is much easier there. In the UK, if donor siblings want to be connected they must, again, wait until they're 18. But in the US, half brothers and sisters can be traced from birth via certain clinics or the Donor Sibling Registry.
The Donor Sibling Registry has been connecting half siblings who choose to be traced since 2000. They currently have 46,354 people registered and have so far connected more than 12,000 people.
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Iori and his donor siblings were contacted via the clinic that processed their donor's sperm. This unique group has formed over the last 12 months and there are plans for a big family meeting some time in the future.
The children and parents often video-conference one another, meet face-to-face and send cards, photographs and presents. There is also a Facebook page created by Magen in Canada.
"It's been wonderful to see all these siblings, the characteristics of them," she says.
"It's been neat to see because you don't quite know which characteristics come from [which parent], especially with a donor. To make that connection, it's quite nice.
"Obviously while the children are all young it's not as interesting for them but as they get older they can see they have these siblings all over the world. So they can travel if they want to, and stay in places for free if they want to," she adds.
But there are opponents to the way in which donor siblings connect. Laura Witjens, of the National Gamete Donation Trust, believes children must receive counselling to prepare them for meeting their half brothers and sisters, which the Donor Sibling Registry does not provide.
While each donor can only be used in connection with 10 families in the UK, in the US there is no upper limit - which she says could potentially lead to hundreds of donor siblings making contact with one another.
"That's a completely different ball game... counselling is important," she says, though the Donor Sibling Registry says its research shows it is not necessary.
For Karena, one of Sam's parents, connecting to the wider family group was a decision not to be taken lightly.
"Even though we had some trepidation about joining a group full of people who were his half siblings, it's nice to [give him the option] to at least know [this family] out there.
"We don't have to be best friends, some of us will get along, some of us may not, but the kids could potentially find one another."
Sam's mother, Anna, says she had a feeling there would be other children out there.
"We knew that the donor would have a lot of other children in the US, so we had no reason to expect [others] would be around the world.
"It's just been a wonderful new dimension."