Mariah Carey tweets about Britney´s yesterday "joke"

Yesterday, Extra asked Mariah her thoughts on Britney’s X Factor role. She said “You think I care about that stuff?” , today she tweet:

@BritneySpears & @SimonCowell of course I luv+care about you dahhlings, congrats! U never know what’s true or gossip,I was joking around!xo

I don´t know why she´s jealous...