Back in 2009 Rick Ross’ baby mama Tia Kemp [not the one who sued 50 Cent] sided with Ross’ rival in the great Rick Ross/50 Cent rap war and used their son to disrespect Rick Ross in the media.

Now Tia is demanding an increase in her child support…

According to TMZ Tia recently filed court docs asking a judge to increase child support for their son William III from $1,951 a month to $2,800 a month because Rick is making more money than when the order was first put in place.

Tia cites Ross’ nine successful Wing Stop franchises, a sparkling wine and e-cigarette endorsement and his hit album “Mastermind.”

Tia also believes Ross violated a clause that states she gets more money if he doesn’t spend enough time with their son.

The case is pending.