Parents are showing 'favoritism'?

Don't worry my sisters 8 and I'm 13 too and the same thing is happening to me just act like your okay with everything and act sad like somethings wrong and when they ask just say why dont you ask annabelle you seem to more concerned with her or something like that then offer to wash dishes or something they'll feel sorry for you trust me it works just be the perfect child except sad parents cant take that! good luck!