Panda-P said

生日快乐！
@BillyG where'd you get that?

@Panda-P and @MichelleMontreal - I know - it sounds terrible - it comes from a "chant" to the old Happy Birthday tune we sang as kids. There is absolutely no offence intended in the words - I think it goes back to the days of post-war austerity in the late 1940's / early 50's when to have mashed potatoes and stew for dinner was a real treat...... something you only got on really special occasions - so you could dispense with the bread-and-butter.... but, who really knows?
Being a chant used by children - yes - there *are* some horrid versions that we would mock the birthday person with - but I wouldn't repeat those here !!!!!!