New Delhi, June 8 -- When Marharyta Nekhoroshyva first saw her newborn son, she was gripped by fear. Born after just 26 weeks of pregnancy, he weighed only 940 grams (2 pounds) and wore diapers no larger than the palm of an adult hand.

"The doctors told me that if he survived the first three days, everything would be OK," she said, tears filling her eyes. "I don't believe in God, but I was praying."

Now 9 months old, Mark is energetic and lively, but he has chronic breathing problems and requires frequent hospital stays.

Nekhoroshyva must navigate her son's illness while living under the constant threat of attack in the Ukrainian city of Zaporizhzhia, where hospitals board up their windows because blast waves from Russian strikes routi...