 Pchilka was born in Hadiach, into the family of a local landowner Petro Yakymovych Drahomanov.She received a basic education at home and completed her education at the Exemplary Boarding School of Noble Maidens (Kiev) in 1866.She married Petro Antonovych Kosach sometime in 1868 and soon moved to Novohrad-Volynsky, where he worked.