Note that the German sentence is negatively connotated.
What exactly does that mean, and how do you know?
By "negatively connotated," wataya means that this sentence would be taken similarly to an insult or put-down. I gather from this that it is similar to calling someone "special" (meaning weird, odd, or mentally challenged) in English.
Oh, okay. But what makes you aware of this connotation in this sentence?
"Ihr" cannot be the courtesy form here?
"Her", "their" and "your (formal)" are equally correct.