DS (6) has been displaying very ungrateful behavior lately and I'm not sure if it's an age thing or if this is becoming his personality. Here are some recent examples: We bought the Lego advent calendar and him and his older brother take turns each day building the toy. He is constantly complaining that his older brother has gotten all of the bigger toys to build each day. Today at his class party they played a game where they unwrapped a ball of saran wrap and got little toys. He almost had a meltdown because he wanted to trade the pencil he got for a different toy and none of the kids wanted to trade. I tried to explain that he should be thankful that he received a gift (pencil) at all and that he shouldn't complain but he just continues to sulk.
How do I correct this? I really don't want him to become someone who doesn't appreciate the things he has.