“The threat of death was always nearby,” Vladimir says. “There were four wards in her specialized clinic and Anya was the only one out of the girls who were there with her who survived.”

Although it can be treated with transfusions and antibiotics, the only real cure for aplastic anemia is a bone marrow transplant that usually comes from a brother or sister.

“As her parents were willing, we recommended they try to give birth to a brother or sister so Anya would have a chance at a transplant,” pediatric hematologist Aleksey Maschan said.

The Sorokiny family decided to once again have a child, even though there was no guarantee the next child was going to be a match. Now by a stroke of luck they ended up having twins – Zhora and Sasha. Then the parents got the news that they had been waiting for – doctors told them that Sasha was a match and that the operation could go ahead.

Yet there was a little cause for celebration – instead of one child at risk of dying; now they had two.

“It was terrifying. It was a unique case because Sasha was so young – only 10 months old – but we could not wait any longer. There is nothing I can compare the feeling with. I have never been through anything like that,” Vladimir says.

Donor babies – conceived to help a sick brother or sister – are something medical ethics wrestles with worldwide. But in Russia there is no bone marrow register, so finding an unrelated donor can prove timely and costly.

“Treatment of children with blood problems is more successful than it was 20 years ago. But we have still got a long way to go and to improve,” says Aleksey Maschan.

Thankfully the operation was a success, and both girls have fully recovered.

“My recovery depends not on me, but on Sasha. I love my sister so much and my family for getting me through this,” Anya says.

Anya was lucky. The introduction of a bone marrow database, which there is now increasing calls for in Russia, would ensure that people like her have a better chance of a cure.