Would you be offended?

My friends and I were at our lockers and we were talking about her daddy because it was his birthday and he had been murdered like 8 years before. So a little kid came up and he told her something and her response was man forget you and he said your daddy. She didn`t hear him because she walked off but I got in his face because she is one of my best friends. I told him you know her daddys dead? He just said thats not his problem and walked off but se ran so I couldn`t go after him. That made me really mad because he doesn`t need to be saying that to people because he doesn`t know who`s parents are dead or not.