Toddlers.

Alicia • Mommy of a 3yr old prince and a 2 month old princess
My son is 2 1/2 and will be 3 in december. He just learned the word MINE... Now everything is "mine" and tantrums come after I take away whatever item he claims is his.. That hes not suppost to have.. Hes an only child and his little sister will be here soon. I am terrified he will become so jealous. What can i do to lighten the load of becoming a sibling for him.