You met the 4 turtle brothers a few months ago. All of you guys became best friends over those months, and you became closest with Donnie. You even learned Ninjitstu and helped them fight.

While all of the boys were distracted watching TV, you went into Donnie's lab. You know he never lets you in there, but the only person- or, well, mutant- you knew that wouldn't tell anybody else was Timothy. While you were Talking to Timothy, you didn't notice Donnie walk in. He noticed you, and heard you talking to Timothy. Usually he wouldn't eavesdrop on you, since it was personal stuff, but he heard his name and decided to stay and listen

Donnie: Well...that's quite a lot of stuff you said about me.