The problem isn't just the child's safety, I want to know what scum is complaining about a display of the American flag, and why civil liberties groups aren't up in arms about it? What has become of our country when immigrants can threaten harm to anyone that displays patriotism, and we cave in to it?!
How do you know it was an immigrant? My ex and her family are pretty passionate about St Patrick's Day and I think their great grandfather was the immigrant. In fact, they go so far as to yell supportive cheers and sing songs for terrorist organizations and root them on in recovering Ireland's "Fourth Green Field". (Personally, I think they really do all that just as a celebration of getting drunk, but who am I to comment about their true passions.)
(And, for the record, I'm not actually anti-Irish. In fact, I guess I'm not really anti-ex's family, even though there are some things about them that are really, really annoying.)