Haruki hears about Kazusa's moving from her mother, who she hadn't been on good terms with.  He feels betrayed and angrily confronts her.  But his words force open the door to Kazusa's heart, which she had desperately tried to keep closed so that the three of them could stay together.
Happy birthday.
Sorry.
I won't be able to come home again this year.

-Youko
Alles Gute.
Entschuldige.
Ich werde auch dieses Jahr nicht nach Hause kommen können.

-Youko
Feliz cumpleaños.
Lo siento, no podré ir a 
casa este año.

- Youko
Feliz cumpleaños
Lo siento.
No podre ir a 
casa este año.

- Youko
Feliz aniversário. Desculpe, este ano
também não poderei ir. Youko