Argue Again

Why my elder sister always argue with me.. just for an --air-cond.... The technician was there too... watching us quarrelling... what a shame!!! She love to argue for a nonsense thing she always want to win so what ... I cannot said something about her weakness... exp: she cannot stand the mild smell of silicon glue even from far far distance.. then she fight back. she: why you want to install air-cond? me: too hot cannot stand she: you are so weak hot weather also cannot stand! Don't know how to endure bitterness... me: that's father plan okay.. I just said to him it was hot in the room not ventilated... she: don't find any excuses okay... that's what you want dad to buy for you me: is there anything wrong to install a new air -cond..? she: you are really wasting of money... buy this and that.. then wanted to buy e book reader some more blaa..bla.. In a nut shell I really don't know what is the reason for her to always argue with people(especially me..) you know actually she also wasting money... she is going to spend thousands of ringgit for her Hong Kong trip....