Im dating my nephews dad?(No blood relation to me) Whats the harm? Im in love, but is it bad for the kid?

You were young and you still are. As a sister of 4 sisters, I have to say that you are very selfish. You're not only being unfair to your sister but to your niece. You leave both of them with no choice. You never had a kid before you don't even know how hard it must have been for your sister. It was a one night stand, but Mandy is not a one time thing. She is here and she's happened. Your sister could have been selfish enough to abort knowing that Kevin didn't love your sister but she kept it and here you are having an intimate relationship with him. Just because she had a one night stand with him doesn't mean that you and him have something greater. She had his kid do you understand? If he weren't ready for a kid, he shouldn't have had with her and especially without protection. You, 19 and already wanting to marry instead of talking about going to school and getting an education. I don't even know if you're thinking about yourself less than you are already about your own family.