I have a granddaughter almost 4 years old who refuses to be potty trained. She is very articulate. Many different methods have been tried since age 2 with long breaks between attempts. Sitting, staying home, no privileges, no toys, cleaning up own mess, etc.etc. have no effect. She is well behaved in most other areas. Sometimes aggressive with 18 mos. old brother but not abnormally so. They live 2 hours from us. What should the parents know to be more successful with this?