Anne's answer for everything

If you ask Anne why she did anything ("Why did you throw that on the floor?" "Why did you make a mess?" "Why did you give that to Winnie?", etc.) her answer is always:

"Cuz why come."

??

Where did she get this from? I think it's a combo of when I used to ask her why she did something, she's say "Cuz". Then I'd say "Because why?" and then her answer always became "Cuz why" when I asked her. Maybe she threw in the come part because I sometimes say "How come you did that?". Who knows how the mind of a toddler works. We're currently trying to explain that "Cuz why come" is not a sufficent answer for why she smeared cottage cheese on her face during breakfast.