Is the definite article in "the church" required? It can be omitted, although it changes the sense of the sentence.
No, it's not. "Girl" is systematically translated by "Dziewczynka". Don't you see the problem?
dziewczynka is translated to girl because it means girl. little girl is mała dziewczynka. Of course English does not have two words for younger and older girls, but it also has one word for ty and wy.