Answer: Children of Zero.
Mr. Harry has 4 daughters, each has a brother ... How many children does Mr. Harry have?
If we read this puzzle clearly, it is said that ...
Mr. Harry has four daughters and a daughter, a brother ...
"HAD" is a thing of the past, but the question is about the current tensions.
So, right now, Mr. Harry has no daughters or sons.
Therefore, the required answer is zero children