Hurtful Comments

When people find out my son is adopted, I have been asked if I am going to, "have any of my own kids" or who is "real parents" are! He is my own and I am his real mom! We may not share the same genetics, but he does not mean any less to me just because he is not my biological child. How have you responded to hurtful comments about not having biological children or being your child's "real parents"?