I think Callahan is alright. A nice, Irish name. It does however sound a bit like a surname.
― Anonymous User 7/23/2020
3
Dirty harry Callahan, tommy boy Callahan, strong Irish surname. But I have also seen it as a given name. It kinda makes me think that with someone with it as a first name I would be afraid they would get bullied. It sounds rich and snobbish for a first name but as a last family name its perfect.