Child support for grown up kids

[Challenger]

Hi, asking for a friend here.
Child is late teen, custody with friends ex, and friend paying full table amount.
The child is in uni and there are 4 more years till support ends I.e. when child becomes 23 or gets degree. Now “child” doesn’t live with ex, and instead practically moved out to start own “adult relationships”, with occasionally visiting ex, but probably even visits would end soon. Does friend still have to pay support, when his ex doesn’t take care of a child?

[rockscan]

If friend can prove kid isn't living with ex even for summer months then there is an argument to stop support. Who is paying for kids' living expenses?

[Challenger]

Both parents pay for Uni. For little things like transportation and eating out kid has few shifts a week to self support, so as for clothing (cheap, but still, it isn’t mom who paid for it ever since kid turned 16, despite CS it and sounds odd, but friend was venting out on this). I would imagine mom pays for food when child visits her, but so does my friend.
How many days a year kid should stay with his ex to loose CS eligibility?

[rockscan]

Technically if they live away from home it is four months of summer. Mom could argue they need to keep a room for kid but if kid has moved out then no support is paid as they do not remain at home.

[StillPaying]

If child is still a "child of the marriage", then your friend would be paying child support regardless. He can try the fight that ex isn't supporting child and money should go directly to child, but good luck with that.

[Challenger]

If child is still a "child of the marriage", then your friend would be paying child support regardless. He can try the fight that ex isn't supporting child and money should go directly to child, but good luck with that.

That’s how it actually started. Kid after years of ignoring dad/my friend, reached out to ask for money. My friend doesn’t mind supporting kid, but he already pays his ex CS and can’t afford to pay both ex and the child same amount. I guess to extent it is a lesson to child for ignoring the dad.

[StillPaying]

Moreso a lesson to parents to act accordingly.