T.D.
Try monitoring how often you are telling her NOT to do stuff. I find with my children (3,3,2, & 8 months) that the more I tell them not to do stuff, the more they want to do it. But I find that when I spend the day praising them for what they are doing right, they are more likely to want to do that. For example, next time she is playing with a crayon, make a point to tell her that she is doing a great job of not putting the crayon in her mouth. Also, you should probably save the crayons for your "alone" times with her so you can catch her before she does it and praise her over and over for what a good job she's doing. If she does stick it in her mouth, that's the end of coloring time. Don't make a big deal out of it, just go on to a different activity. Same with the dog. "Catch her" petting him gentle and REALLY praise her for it. If he's friendly, let her give him a treat or two a day. Spend the day looking for things she is doing right and praise her immediately for it. Chances are she will go out of her way to show you what a big girl she can be. It is a daily battle for me and I know I've lost when I spend the day telling them "no" and "stop that". Also, don't wait until you are sans baby to play with her. Let her sit next to you while you are feeding your son and use the time to point out that he's her baby brother and he's got 10 toes and 10 fingers and 2 eyes, etc. Have her "help" you get wipes/diapers/clothes during diaper changes and tell her what a good big sister she is. Go out of your way to think of ways she can "help" you. Basically I find that it is just a matter of trying to find ways to redirect their energy. Good luck!