Roughly 159,000 American children were both adopted and waiting to be adopted in 2014, according to the U.S. Department of Health and Human Services "My job is to make the baby feel safe and loved 24/7," veteran interim caregiver Susan Singer told ABC News. "I hold them all the time. I talk to them. I sing to them. We play music. And I get so much joy and pleasure. I feel so good when I'm with an infant that I hope that it does…something for them too."Prospective interim-care providers must first submit to background checks and home visits to ensure the babies are going into safe environments, ABC News reports . In addition to serving as temporary surrogates, the job also involves consoling communication, ensuring birth mothers as well as prospective adoptive parents that their babies are safe, happy, and healthy.Knowing from the outset that the babies will remain only in their care for a matter of weeks eases any separation anxiety that might arise, spokeswoman for New York's Spence-Chapin adoption agency Katherine Foley told DNAInfo Even if someone can't host a baby in-home, many adoption agencies continually need volunteer staff members and people to rock and cuddle the babies to provide caring contact that's crucial for healthy early-childhood development."All agencies over the years have certainly needed volunteers," Adam Pertman, president of the National Center on Adoption and Permanency, told ABC News. "But…the need has grown. Volunteers have become more and more essential."