Kyiv, Ukraine (CNN)When 12-year-old Kira Obedinsky, orphaned by war, was whisked from her hometown of Mariupol to a hospital in a Russian-controlled area of eastern Ukraine earlier in March, she was unsure if she would ever be reunited with her remaining family members.

Now in Kyiv, against all the odds, she sits on a hospital bed with her grandfather Oleksander Obedinsky -- and on Wednesday spoke to CNN for the first time about her ordeal. She continues to recover from injuries that nurses say include shell fragment wounds to her face, neck, and legs. Her scarred face and introverted manner are signs of the physical and psychological trauma she has suffered.

The Obedinsky family has been torn apart by this war. Kira's father, Yevhen Obedinsky, a former captain of Ukraine's national water polo team, was killed on March 17 as Russian forces shelled the city. In that moment, Kira was orphaned, her mother having died when Kira was two weeks old.

Days after her father's death, Kira was taken to a hospital in the Donetsk region by Russian-speaking soldiers after sustaining injuries from a landmine while trying to flee Mariupol with her father's girlfriend.

“The [Russian] military came running; they stopped two cars and took us to Manhush, to a hospital because we were bleeding. Then they took us from Manhush to another Donetsk hospital,” said Kira.

Speaking to CNN earlier this month from Kyiv, Oleksander told CNN that he feared he would never see his granddaughter again because it was almost impossible to travel across the war-torn country to retrieve her. He said he had spoken to the hospital where Kira was being treated and was told she would eventually be sent to an orphanage in Russia.

Their grateful reunion, more than a month after they had last seen each other, was orchestrated by negotiators from Ukraine and Russian -- and involved an epic international journey.

On Tuesday, Ukrainian President Volodymyr Zelensky visited Kira in the hospital to celebrate her return, also giving her an iPad to entertain her as she recovers.

Oleksander said he had told Zelensky that Kira was "tired but happy” and thanked him for the safe return of his granddaughter. "Nobody believed [it would be possible]. But thank God we managed,” he told CNN.

Retrieving Kira from territory controlled by Moscow-backed separatists was no easy task. Following media coverage of her plight, the Ukrainian government told her grandfather they had reached an agreement that would allow him to travel to Donetsk to pick up his granddaughter -- but that it would not be an easy undertaking.

Undeterred, Oleksander immediately embarked as instructed on what was to be a grueling four-day journey, taking a train to Poland, a flight to Turkey, a second flight to Moscow, followed by a train ride to the southern Russian city of Rostov, before finally reaching a tearful Kira after another car journey to Donetsk, he said.

After an emotional reunion -- with countless tight hugs, they said -- the pair then set off home, taking the same protracted route on the return leg to Kyiv.

“I missed him”

In Kyiv's Okhmatdyt Hospital, Kira cherishes the one possession of her father's that she managed to keep after he died: his cellphone. It was her sole link to her family while in Donetsk.

She had contacted Oleksander -- her only remaining blood relative -- by logging onto Instagram and sending messages to her grandfather's girlfriend to explain where she had ended up, she said. Instagram posts from February showed Kira posing innocently for selfless, blissfully unaware of how life would be upended in mere weeks.

Having that bond to her former life was crucial for the young girl as she found herself in a Donetsk hospital surrounded by unfamiliar faces and yearning for her grandfather.

“I was glad I could call them. I don't know how much time had passed,” Kira sighs, adding: “I waited a long time for him to pick me up. Even in the second hospital, I waited... I missed him.”

The pair was reunited on April 23, Oleksander said, having last seen each other on March 10. He's painfully aware that he would have never been able to ensure both his and Kira's safety if he'd attempted to retrieve her alone, without the Ukrainian government's assistance.

“I wouldn't have dared to do it myself, of course. Because this venture could have ended with neither me nor Kira being released,” Oleksander said.

While in Donetsk, Kira was interviewed by a Russian state media channel that broadcast a video of the young girl talking happily about how she was sometimes allowed to call her grandfather. The interview had been used as “proof” that she wasn't abducted, according to one Russian TV presenter. However, Kira paints a very different picture of her experience.

“It's a bad hospital there,” she told CNN. “The food there is bad, the nurses shout and the hospital is not good.”

Weeks later, Kira has recovered from some of her injuries but she painfully remembers when shrapnel was removed from her body.

“I was taken to Donetsk by ambulance at night; they took shrapnel out of me at night. From my ear, I screamed and cried a lot because I felt their manipulation in my ear. Here it was on my face, on my neck, and on my legs,” she said.

Hiding in Mariupol ruins

Now safely in Kyiv, Kira is also able to reveal exactly what had happened back in Mariupol and how the family's luck ran out when they tried to escape the city that was rapidly becoming encircled by Russian forces.

She recounts living amongst shelling and “loud bangs,” hiding with her father's girlfriend Anya and her children between the ruined walls of their home. Tanks rolled into the street, Kira said, and she remembers seeing men in military uniform approaching their yard.

Kira says that after her home was shelled on March 16, the family was trapped in the cellar, with neighbours helping to pull them out of the rubble. Her father never emerged. For three days, Kira, together with her father's girlfriend and her children, sought shelter in another cellar before attempting their fateful escape from the city.

It was Kira's friend who kicked a mine while running, she says. Kira recalls that her ears were bleeding afterward and that the family friend's dog absorbed most of the blast. The group survived but sustained shrapnel injuries.

Kira said this was when Russian forces -- alerted to the group's whereabouts by the explosion -- picked up the group and drove them to the town of Manhush for immediate treatment at one hospital, and then on to another in Donetsk in an ambulance, where the group was forced to split, leaving Kira alone, wounded and terrified while the others were taken elsewhere.

The ordeal is a world away from Kira now as she plays games on her new iPad while absently talking about downloading more apps to play music, and voicing her excitement over reuniting soon with her grandfather's girlfriend.

As the family starts the process of returning to some semblance of normality, the fact that they are, to their huge relief, together once again is not lost on them.

“I still can't believe that it finally happened. Because we believed it, but many said it was impossible. It was a really difficult process,” said Oleksander.

They say they have been bowled over by the efforts of the president in their case -- one that garnered worldwide attention.

But for Zelensky, Kira is just one of many Ukrainian children he says have been deliberately deported to Russian-controlled areas. Moscow, meanwhile, has denounced claims of forced deportations as lies, alleging that Ukraine has hindered its efforts to “evacuate” people to Russia.

“We are most worried about the children," Zelensky said while visiting Kira on Tuesday. “Children are our future. We will fight for every Ukrainian child to return home.” (CNN)

•PHOTO: Orphaned girl was taken and used in Russian propaganda. Now, she tells her story 02:46

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