The fact that we took your mudblood whore or the fact that you didn't even notice until your ridiculous Aurors found her on accident. Had they not stumbled upon our little hiding place (and we both know stumbling onto something like that takes all of the skill of a child) would you ever have known that we upgraded your precious Mudblood?
You should be thanking me and asking for the other one back, at least she had decent bloodlines.