Filia

Filia is a doll who appears in Dawn of a New Day (Part 1) when Lena finds her in an old box. Lena asks her mom Mila if Mila remembers when "dad" gave Lena the doll, and Mila says yes. Lena then elaborates "he thought she looked just like me, right" and Mila affirms "yes he did".

After sending the children away, Mila is wistfully carrying around Filia, and sets her down on a windowsill. Observant Oslo notices this, which is how he surmises that Lina had children (though it's unclear how he knew it was plural as that could've belonged to a SINGLE child.

Filia's head is ripped off by Oslo who leaves her on the ground.