The nurse who waved Katia through without looking up, and later mentioned Annie's death in passing at a park.
In Katia's memory, this nurse sits at the station reading an English-language romance novel when Katia hesitantly pokes her head through the doors and says she only wants to say hello to Annie. Without even looking up, the nurse says "Oh, hi Katia. She's having a good day today," and lets her through. It is the moment that makes Katia's Worst Memory possible.
The same nurse delivers the killing blow later. Nobody told Katia when the baby died; she found out only when she ran into this nurse at a park, who mentioned it as casually as if it had not mattered: "Oh, that girl? She passed a few weeks ago." Katia says that in that moment she lost all the hope she had, all over again.
A hospital nurse seated at a station with an English-language romance novel open in front of her, attention on the page rather than the visitor.
The indifferent bystander who both grants Katia her last visit and casually reports Annie's death.