Re: This chair Mama!
Welcome! Sounds like you have a typical toddler on your hands.
Whether or not you lay down the law on the chair is really up to you. With a toddler, you end up in a sort of give-and-take situation. Sometimes you stand firm, sometimes you yield. There's no one right way to do things, and sometimes bowing to your child is a good thing. Maybe you could see this as a teachable moment? Like if you say "I will sit down in the chair if you say 'please'"- then you're teaching him that manners will help him get his way.
Coolest thing my big girl said recently: "How can you tell the world is moving when you are standing on it?"
Coolest thing my little girl sang recently: "I love dat one-two pupples!"