My son just found out who his real father is.
Why didn't your son know who his father was?
I didn't want him to know the truth.
It's not good to lie to your son about who his father is because he deserves to know the truth. I think you should apologize to your son for lying to him all these years, and answer any questions he might have about the situation.
Why would I apologize, I don't care about him that much.
Do you really not care about your own son? I think that's an awful thing to say. How would he feel if he saw that message?