FernandasMum, both. My 'esposa" is more formal and my 'mulher' is more common. But both are completely normal.
i made a mistake. I translated this phrase like this: my wife is the mother of my two sons. I shouldn't have use the word two because it is not in the sentence. But, i am right if i translate this sentence like this: My wife is the mother of my sons. You do not have to use the word children. What i mean is that it is right both ways