In Ontario, are you required to pay for a child over the age of 16, who still resides with the Mother, but has not attended highschool full time since they turned 16? Is there an exemption to the "age of majority" child support guideline?

I am paying child support for 2 children- the Ontario child support guidelines state that you have to pay child support until the child is no longer in school, but it aslo says you have to pay child support until the child reached the age of majority. If a child, who is now 17, has not attended school full time since they reached the age of 16 am I still required to pay? This child is capable of working full time if he chooses not to go to school. His Mother also kicked him out of the home for 3 months as he stole property from her and she still expected me to pay her child support. She then put him in a group home for an additional 5 months ( funded and paid through by a government program) and she still expects me to pay. I need to know if there are exemptions to the "age of majority" in regards to having to pay child support