It's absolutely correct to say "Αυτό είναι το παιδί μου" instead of sentences like "Αυτό το κορίτσι/αγόρι/παιδί είναι το παιδί μου". By saying "Αυτή είναι το παιδί μου" you mean "Αυτή η κοπέλα/γυναίκα/etc είναι το παιδί μου"
Why isn't the correct sentence "Αυτη ειναι του παιδια μας" Should "the child" not be in the genitive case as the she is being owned by "us". "She is our child" she belongs to us, no? Why is this nominative?
Waw, I can see confusion here... Because our pupil common sense tells us that το παιδί is neuter and must agree with the pronoun in gender and number αυτό το παιδί..... Then is it correct if you put that female and neuter together or not?
Oh, but how do you say "This dog is small" if the dog is FEMALE, or how do you say "this cat is small" if the cat is MALE? It's a bit confusing, since we learn from the start that nouns kind of have an own genre
"Γάτα" is treated as a female, unless you specifically know it's a male. It's the exact opposite for "σκύλος". "Σκύλα" is the feminine version of the noun, but it isn't really used because it also means "b--tch".