How can I encourage moderation with gifts during the holidays?

Dear Mama Drama: My daughter is three and is starting to understand that the holiday season means presents. I have seen my older nieces and nephews become obnoxious and greedy at family gatherings, throwing tantrums when they don’t get exactly what they want. I’d like to prevent my daughter from being so obsessed. What ideas do you have? ~Moderate Mama (photo credit) Dear Moderate: