Why don't you use bool? :shock:
And why are there two ifs? One is enough.
Besides, I would pass Hello by const reference and store the rectangle given by Hello.GetRect() (you can't be sure SFML doesn't calculate it every time, and even if, this is an implementation detail and might change in the future).
P.S. I found a mistake in my upper post, of course I meant sf::Sprite and not sf::String a second time.