(NEW YORK) -- Matthew and Christy Johnson describe watching the Russian invasion of Ukraine as "heart-wrenching."
The Johnsons, of Littleton, Colorado, are one of hundreds of families in the United States who were in the process of adopting a child from Ukraine when the conflict there began.
"It feels like living through a nightmare," Matthew Johnson told "Good Morning America." "She's not legally our daughter but for all intents and purposes we feel like our daughter is over there with bombs flying around her, and all we can do is pray."
The Johnsons, parents of five biological children, first met the child they hope to adopt, an 8-year-old girl named Margarita, this summer when they hosted her for several weeks through Host Orphans Worldwide, a nonprofit organization that matches host families in the U.S. with Ukrainian children.
Margarita returned to Colorado in December to spend the holidays with the Johnsons, and flew back to Ukraine on Jan. 15.
The Johnsons said they received one of the final pieces of documentation needed for the adoption process just days before Russia's invasion of Ukraine began.
Now, they said they are waiting daily to hear about the safety of Margarita, who lives in southeastern Ukraine.
"Over the past several months we've been able to do video chats or send her messages and packages, but we haven't heard anything [from her] for the last week," said Christy Johnson. "So it's been really heart-wrenching."
The Johnsons said they have heard from other families in the U.S. that the institution where Margarita is staying is safe, but they have no idea what is next for the young girl they describe as "funny and delightful" and a member of their family.
"When she left in January we were telling her, 'We'll come. We'll see you in Spring,'" said Matthew Johnson. "Now it's devastating. We can't fulfill that promise anymore."
While more than 1.2 million people have been forced to flee Ukraine since Russian forces invaded on Feb. 24, millions more people remain in the country, including children.
Prior to the war, approximately 100,000 children in Ukraine were being raised in institutions, according to government statistics, a United Nations Children's Fund, or UNICEF, spokesperson told ABC News.
Many of the institutions are located in hot spots, according to the spokesperson, who added that many of the children in institutions, such as boarding schools and orphanages, have disabilities.
These institutions are being evacuated without proper monitoring of the children's situation, according to UNICEF.
Hannah and Brent Romero, of Villa Platte, Louisiana, said they submitted the final paperwork to adopt a 15-year-old boy from Ukraine on Jan. 17, just weeks before the war began.
The boy, whose name they asked not be used, has Type 1 diabetes, an autoimmune condition in which a person's body no longer makes insulin.
"We ask him every day about that and he says he's doing OK," said Brent Romero. "But I think he's not telling us the full truth because he doesn't want us to worry more than we're already worried about his health."
The Romeros said they are able to stay in touch with the boy -- whom they have known since 2019, when they hosted him for nearly eight weeks in Louisiana -- through text messages mostly while he shelters in place in Lviv, a city in western Ukraine.
"We stay up until he's awake so we can see if we can catch him before we go to sleep," said Hannah Romero. "He told me yesterday, 'I didn't sleep well ... because the air raid sirens kept going off and we had to go in the basement.'"
Hannah Romero, a high school English teacher, and Brent Romero, a pastor, are flying from Louisiana to Poland on Friday to join a group of Americans who have gathered there to help support children who make it out of Ukraine.
Hannah Romero said she plans to stay in Poland for two weeks, while Brent Romero said he plans to stay indefinitely, until he can bring the 15-year-old boy home. The couple, already parents of two sons, said they are also hoping to take in the boy's 11-year-old sister, whom they have never met.
"We're not asking permission to adopt them right now," said Hannah Romero. "We're asking permission to bring them here temporarily, just to keep them safe and until everything else can be figured out."
She continued, "It might take years to figure everything else out, but that's OK. We need them to be safe in the time being."
Hundreds of miles away from the Romeros, in Florida, Kelly Lee, a mom of five, including four adopted children, is working to help a 16-year-old girl she is in the process of adopting get safely to the U.S.
Lee, of Oviedo, Florida, and her husband, Kevin, are now applying for tourist visas for the girl and her sister and 7-year-old nephew, all of whom were able to escape to Hungary.
"The whole [adoption] process is on hold, and it's really just a matter of getting them safe is what's important," said Lee. "Our first attempt is to apply for these tourist visas."
Lee said she has seen what she describes as an "army of moms" working together in the U.S. to help children in Ukraine, connecting on social media and helping each other navigate language barriers and the extreme circumstances of war.
"We're getting messages from families saying, 'We need help. We have this kid we need out,'" said Lee. "So it's been a joke that it's like an army of moms have come together to try to get their children. They're researching in a country that they can't even read websites, but they're trying to figure out buses and trains."
In Oregon, Jennifer Mitchell, is one of the moms leading the charge.
Mitchell, a mom of eight, including three children adopted from Ukraine, is one of the founders of Host Orphans Worldwide, the organization that matches host families in the U.S. with Ukrainian children.
While Host Orphans Worldwide does not facilitate adoptions, about 75% of kids in its program end up getting adopted by people in the U.S., according to Mitchell. She said Ukraine has a high number of U.S. adoptions because it has both one of the shortest wait times for international adoption and one of the largest populations of children in need.
Mitchell's husband traveled to Poland this week to assist a team on the ground supporting refugees, while Mitchell is home in Oregon coordinating between families in the U.S. and orphanage directors in Ukraine.
"We've gotten money to them to buy food because they were running out, and we've helped with bus transportation and train tickets to get kids out of Ukraine," she said. "We have a few orphanages in the eastern part of the country that are surrounded and it is safer for them to stay put than to move. It is a dire situation."
Mitchell said in one of those orphanages is a 12-year-old girl she and her husband were in the process of adopting, noting they have not spoken to her in over a week.
"There's probably closer to 100 kids in that orphanage," she said. "Even evacuating them puts a target on their back."
With no end in sight to the conflict with Russia, Mitchell said she fears what the end result will be for children in Ukraine.
"The orphan crisis in Ukraine was already bad and this, it's just going to be a humanitarian emergency," she said. "It is horrific."
ABC News' Zoe Magee contributed to this report.