Toileting
If normal toilet routines have been unsuccessful you should always contact your GP or school nurse who will check for any medical reasons which may be a factor as to why a child is struggling. Once any medical factors have been ruled out these are useful links which may help.
Sunderland school nursing team 03300031552
https://www.autism.org.uk/about/health/toilet-training.aspx
http://www.theedenacademy.co.uk/assets/uploads/One_step_at_a_time_toilet_skills_leaflet.pdf