I tell my students you have an absolute right to write about people you know and love. You do. But the kicker is you have a responsibility to make the characters large enough that you will not have sinned against them.
Education makes us more stupid than the brutes. A thousand voices call to us on every hand, but our ears are stopped with wisdom.
I love my mother dearly, but it wouldn't be suitable for me to live with her all the time.