This is from the BBC Mr. Stanton

Mr Stanton was a father to a four-year-old daughter and a sports fan.

As I read, "to be a father to someone" drew my attention. I wondered why "...father of...." instead of "...father to..."?

I made some research about differences in meaning between the two, and I learned that "father of" indicates "biological father" while "father to" means "being like a father".

So, why does the "BBC" use "father to"?