A Shoe Battle

It is a battle to get Kelsey and Kaley to put their shoes on in the mornings or anytime it comes to them having to wear shoes with closed backs. They have very skinny heels and no matter what type of shoes I buy them, even narrow width, they slide on their heels and they can't stand it. They have a fit everyday because they can't get them tight enough. I have tried taking each lace out and pulling it as tight as I can and they still go up on their heels. It's so frustrating. I know it bothers them but I don't know what to do about it! They Nike's are narrow width but still slide. Any suggestions to where I can go to buy narrow shoes? I really feel bad for them.