Is this normal!?

So tonight on my way home from the movies with my son I hit a cat (I am an animal lover and I felt so bad).. I got home and told my nephew what happened and he giggled and said womp womp womp.. I was like wtf is wrong with you!? I texted my sister what he said and she just says he is his mother's son lol and I was like it's not funny though and she says it shouldn't have run out in the road, I wouldn't have felt bad... Is that sick to anyone else or am I just over thinking it!? Making your kid heartless like you is probably not a good thing! I'm glad I'm not like that because it's just disgusting behaviour in my opinion!