NOVOSOLONE, Ukraine - On the morning she gave birth, Maria Kamianetska sent a photo of the infant to the baby's father, back in their home village. The boy's eyes were closed, his tiny head covered in a white hat, his body swaddled in a cloth.

"You have a son," she wrote from her hospital bed. The maternity ward where she'd given birth was in Vilnyansk, a town in Zaporizhzhia, one of four Ukrainian regions that Vladimir Putin claims to have annexed.

For the entire nine months she had carried the baby, her country had been under attack, her life - and her son's - constantly at risk.

But here he was, just under six pounds and healthy. The parents named him Serhii. He was their fourth child, the little brother their 7-year-old son had been waiting for.

But the baby's father would never have the chance to meet him.

At about 2 a.m. on Wednesday, as Kamianetska had just finished nursing the child and laid him down to sleep in the crib beside her, a rocket crashed into the hospital's maternity ward. The hospital walls came crumbling down, trapping Kamianetska and her infant in the rubble.

They were the only patients in the ward that night. Rescuers pulled the mother out of the rubble alive, her legs scraped and bloodied. The only person killed was baby Serhii.

One of the youngest casualties of the war, 2-day-old Serhii was among the more than 440 Ukrainian children killed and hundreds more wounded so far as a result of Russia's invasion, according to the Ukrainian prosecutor general's office. The boy did not live long enough to be given a birth certificate.

As rescue workers searched through what remained of the maternity ward, they told Kamianetska they couldn't find a baby.

They found only a doll, they said, lying face down on the ground.

"That's my son!" she shouted.

Kamianetska had always wanted to have a fourth child - a boy, she hoped. Her 7-year-old son, who had grown up with only sisters, was already collecting his toy tool box to show his new little brother. He yearned to be a tractor driver like his father and couldn't wait to share his child-size tractor with the boy.

The parents, who spoke to The Washington Post this week, had everything ready for Serhii: The crib, the stroller, the clothes. Kamianetska and the children's father, Vitalii Podlianov, were preparing to move across the street in their small rural village to a bigger house in the spring, to have more room for their growing family.

The couple had learned they were expecting a baby in late February, just as Russian troops were beginning their assault on Ukraine. As millions of Ukrainians, many women and children, fled the country, Kamianetska and her family stayed in their village, Novosolone, in the Zaporizhzhia region. This was their home, the place where they had raised their three other children and where the rest of their family lived.

But it was also a region with a name now recognized around the world, Zaporizhzhia, the site of Europe's largest nuclear power plant and a likely location for a new Ukrainian counteroffensive.

Missile strikes had become increasingly frequent in the area near the hospital. Before November, the town had experienced no strikes, its mayor said; this month it's been struck on three different days. Ukrainian President Volodymyr Zelensky on Wednesday blamed the maternity ward strike on "the terrorist state." Russia's ministry of defense did not respond to a request for comment.

Kamianetska lived just about an hour's drive from the front line, yet somehow the war felt far enough away. "The explosions in the distance didn't worry me," she said. But as she prepared for Serhii's arrival, they inched closer and closer to her town.

She had seen the images of bloodied pregnant women on stretchers outside a Mariupol maternity hospital - photographs that shocked the world early on in the war.

But on the night before her baby was born, her only concern was making sure she could get to the hospital safely. Podlianov had driven her to stay in the home of a relative in the town where she planned to give birth, which was closer to the hospital than her home. He then returned to their village, to work and care for their other children.

Early Monday morning, Kamianetska called an ambulance to rush her to the hospital.

The baby came after only two contractions. He was born at 8:20 a.m., less than 20 inches long.

It was past 1 a.m. when she heard the first loud crash - a strike in a different part of town. Then came the blast.

The rocket crushed the brick walls of the second-floor maternity ward, sending it tumbling onto the clinic beneath it, where a trapped doctor cried for help, she recalled.

A piece of the concrete ceiling landed on top of Kamianetska, who was lying in bed in only a nightgown. But she remained fixated on reaching for Serhii's crib.

She screamed for help, as she tried desperately to lift off the pieces of concrete to reach the baby. She recalled her lungs filled with smoke and dust.

She managed to lift herself off the bed and lunge toward the crib. The mother was horrified to see it was empty. The baby had been launched from his bed in the blast.

Kamianetska grabbed her phone, using its light to search for the infant as she walked through the debris in her bare feet.

The moments that followed are all a bit of a blur: The rescue workers pulling her out of the rubble through a window; nurses pulling the shrapnel off her legs; the phone call to her mother, telling her the maternity ward had been hit by a rocket.

What she remembers, vividly, was her own screaming, her pleas for her son.

About 15 people gathered in the cold cemetery Thursday as the priest approached the white lace-trimmed box in front of them. He said a prayer and placed a cross inside the tiny coffin - less than three feet long - where Serhii lay, covered in a blue blanket. The baby's eyes were closed, his face still covered with small scrapes.

The funeral had come together quickly, just a day after he died. The parents didn't want to bring the coffin into their home, where their other children would see it, so they needed to bury the baby as soon as they could.

Serhii's older siblings all stayed home, playing in the front yard, as their family members rushed to the cemetery. The children knew their youngest brother would not be coming home after all, but the parents had not yet explained why.

Wearing thick coats in near-freezing temperatures, relatives arrived carrying flowers and toys - a stuffed tiger and red lady bug and a brand new toddler-size car. Kamianetska wore a black winter jacket. On the back were the words: "Everything will be fine. It will be even better every day."

Kamianetska stared longingly into the box, lurching toward it as she wailed. Her mother and sister-in-law grabbed her by the arms, helping her remain standing. She leaned over into the coffin and gently kissed the baby.

Then, after the priest had sprinkled water on the coffin, two men carefully lowered it into the ground. The sound of shelling rumbled in the distance as the family members sprinkled dirt in the grave.

As men covered the casket, the mother recounted what happened that night.

"My room was completely destroyed," she said. "I was looking for the child in the rubble. . . . The child was just in the crib. I was thinking of changing him, and then this happened."

Each of the relatives hugged her, urging her to be strong. As most of them left, her mother gave Kamianetska advice on what to do with her breast milk, now that she would not be nursing.

That night, Kamianetska dreamed of her son. In the dream, he was hungry, and wanted breakfast. So the following morning, she returned to the cemetery to bring him cookies and chocolate.

This time, she brought the children along to the grave, to meet their baby brother for the first time.