Child support at 18 yrs

Child turned 18 who is still in high school… his girlfriend is now living with him and his mother
…are we still obligated to pay for support with girlfriend who is 20 living and working and “playing house” in the home?
Thank you

NC Gen Stat § 50-13.4 (b)(2) states: “If the child is still in primary or secondary school when the child reaches age 18, support payments shall continue until the child graduates, otherwise ceases to attend school on a regular basis, fails to make satisfactory academic progress towards graduation, or reaches age 20, whichever comes first, unless the court in its discretion orders that payments cease at age 18 or prior to high school graduation.”

You are still obligated to pay child support until your child graduates from high school. The fact that his girlfriend lives in the house does not automatically terminate a child support obligation.

Thats what i figured i was just double checking
Thank you for your time