Twinless Twins: The Unique, Heartbreaking Grief of Losing a Twin Sibling

Her non-identical twin sister had been strangled by Sharon's estranged husband Philip, who then killed himself at another location. "I was immediately hysterical," Siobhan tells me. "But then it turned into feeling a lot of anger, followed by a big profound sense of loss. At first, I just kept thinking that I'd lost her and would have to go and join her again. I had a lot of counseling to deal with that specific trauma."

Born just 11 minutes apart (Sharon was the oldest), the pair had an incredibly close bond. "We spent almost every waking moment together since we were born—partners would say there were 'three people in the relationship,'" she says. "We had seen and done so many things with each other. Two of our children were born just six days apart. We worked at the same place and went for lunch every day. Sharon was the one person I would have phoned in any situation and I just didn't have that anymore. At the start it was so difficult to get over."

Siobhan is one of thousands of twinless twins round the world—defined as somebody who lost their twin whether it be in or around birth, during childhood, or during adulthood. The sense of loss is so intense that even those whose twins died at birth or in the womb (known colloquially as "womb twins") can remain profoundly affected. Elvis Presley was one famous example—the stillbirth of his twin brother is said to have haunted him all his life, while pianist Liberace said the death of his twin in the womb fueled his flamboyant lifestyle and desire to "live for two."

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"I've always known I was different," Olga, from Dublin, Ireland, says. "I had abandonment issues, and even though I had siblings I had a real sense of always being alone and isolated from other people. It really felt like there was something missing." After finding out that she had lost a twin at birth, she joined the UK-based association Womb Twin and now helps to run conferences bringing other womb twins together.

Other organizations that help twinless twins exist too. In the US, the Twinless Twins Support Group is the major source of advice and support, while Siobhan has found help from the Lone Twin Network over in the UK. Founded out of a research project conducted in the 1980s by a twinless twin called Joan Woodward, the LTN now has over 600 members who meet at support groups and talk on Facebook.

"Last year, I saw a documentary about people who lost their twins in 9/11 and one of them mentioned the Twinless Twins network, so I wondered if there was a UK equivalent," she tells me. "I was so happy to have found there was—the LTN have helped me so much. I know when I'm feeling really down I can post things that nobody except for other twinless twins, who know exactly what you're going through, can see. People who've lost their twins know there's a deeper connection there."

In September this year, Siobhan will be flying to Edinburgh to attend her first support group in person. "It's a hard month, as it's coming up to the anniversary of my sister's death, so I know being there with other twinless twins will be really good for me," she adds.

The ongoing Fullerton Twin Loss Study describes the twin bond, especially among identical twins, as the "closest and most enduring of all human relationships."

"The grief 100 percent feels different to other forms of grief," Olga says. As well as running the conferences, she works part-time as a life coach and counselor, mainly working with twinless twins. "There is a real difference with people losing their twin. The feeling that something is missing goes deep into your DNA—they need specific therapy."

The Fullerton study also indicates that out of the different types of twins, identical twins feel bereavement more keenly. One of the reasons for this could be down to the way that the surviving twin looks exactly like their lost sibling—a permanent reminder of the person they've lost.

Despite the fact that Sharon and Siobhan were technically non-identical, they looked very similar. "As babies, I was always dressed in pink and Sharon in yellow, as my dad couldn't tell us apart," Siobhan says. "Even in adulthood he couldn't at times, and people in our office would talk to us thinking we were the wrong person all the time."

Now, she says, her looks have "definitely made things harder."

"There were times when I walked into the house with my hair tied up—Sharon wore her hair up a lot more than me—and my dad got really upset. When I visited our old office too, the receptionist would take a deep intake of breath," she says. "In the beginning too, Sharon's children would stare at me. In some ways it's maybe been comforting but mainly it's a really difficult reminder."

Birthdays can be another prompt of the twin who's been lost. "I was worried about celebrating our 40th last February. Sharon and I would sometimes celebrate together—we had a big karaoke night one year," she says. "She was so into partying I knew she would have done something, so I realized I had to." In the end, she chose a birthday cake with a picture of the two of them on top.

These days, Siobhan is carrying on with the healing process. She still has counseling to cope with her loss, and often visits places she went with her sister to feel close to her. "Sharon hated cemeteries, so even though she's buried nearby I prefer to go to places we went to together—various areas of Belfast where we had fun times, and our old office is good about letting me come to a meeting room and sit quietly.

"It sounds really bizarre, as I have my husband, a close family and loads of friends around me, but I sometimes just feel really alone," she says. "Even now six years has passed, I feel like there's nobody in the world who can compare to the relationship I had with Sharon."