It's not too late, but you've wasted a lot of time doing the wrong thing with this girl. You need to work together on this, and not allow her to play one of you against the other. First, don't give her anything else. Obviously, she doesn't appreciate what she has. Of course, she will throw fits and tantrums, because that's how she manipulates you. Make her use what she has and don't buy her things to appease her. If you and your husband have to run errands, make her go with you--barefoot or not. It's her choice if her feet get sore, if the weather's cold, or whatever. If she whines and complains, ignore her. Talk to each other, and not her. Tell her you're not fixing her hair for her. If she refuses to fix it, then she will go to school with messy hair. Absolutely do not give in to her demands. Of course, the other kids will laugh at her, but that's not YOUR problem. She will eventually do her own hair. Give her the ipad only to do her homework, and then take it and lock it up. Literally. She not only can learn to do chores around the house (which I suspect she's never learned to do, since you've always given in to her), but she will learn that if she doesn't do them, they won't get done. For example, she's going to put her dirty clothes in the laundry instead of your picking up after her. If she refuses, pretty soon, she will run out of clean clothes. If she refuses to wash the dishes, let them stack up until they smell. It will be tough on you and your husband for a little while, but this is the only way she's going to learn. When she starts throwing a tantrum, march her to her room and turn around and walk off. Don't buy into her fits. You and your husband together sit her down, and tell her there will be no allowance, no telephone conversations with friends, no going anywhere except to school and back, until she decides to make better choices. Prepare to have her scream that she hates you or whatever she's done in the past to manipulate you. If you change your behaviors toward her (not giving in to her demands and letting her tantrums roll off your back), pretty soon she will catch on that the only way she will get anything positive in her life is to learn to do what's asked of her. Oh, and by the way, quit asking nicely. Start being nasty the first thing in the morning by demanding that she get up, fix her own hair, get to school on time, etc. Keep the nasty attitude every waking minute until she begins to relent. It will be very hard for you to do because you've tried the other approach for so long. Just remember, that hasn't worked for you, and this approach will. Trust me. Keep telling yourself that you're the parent, you're in charge, and you're going to make it work for you. Oh, and if you and your husband can find a parenting class in your area, take it. It will help you to get strong and stay strong. Good luck.
licensed school psychologist