She's been squealing and screaming all day, "Mine, mine, give it to me!" It doesn't matter what she…

She's been squealing and screaming all day, "Mine, mine, give it to me!" It doesn't matter what she has in her hands or what's nearby – she demands it. I can't even eat in peace because she's always trying to snatch things away. If there's anything I can share, like a bite of soup or potato, it's usually nothing. There's a phone on the table – "Mine, mine!" A mug of tea – "Mine, mine!" She sees a comb – same thing. And she screams so loudly that my head sometimes aches. My son never acted like this, but this little girl is something else. How long will this last? Will it only get harder? By nighttime, my head is spinning from all the shrieking.