The ship's crew members speak Swedish and Finnish. When Sister Evangelina climbs on the ship you can hear the crew members say in Finnish "varovasti" multilple times which means "careful". The man who gives the daughter a cross around her neck says in Finnish: "Pidä itsestäs huolta siellä ja koita olla rohkee." Which translates to English as "Take care of yourself in there and try to be brave." However, the English captions, on Netflix at least, claim the man is speaking in Swedish.
The song the ship's crew sings when they hear Kirsten's baby's first cries is the traditional Swedish birthday song "Ja, Må Han Leva!"