Who should be responsible for transporting kids

my ex and i have been separated a little over a year. he moved in with a girlfriend 20 miles from here at that time. we have a verbal agreement that he picks up the kids every other weekend and has them for 2 nights. lately, he has been expecting me to pick up the girls on sunday evenings, claiming i should do it because he pays child support. i am not the one that decided to move so far out, and i don’t always have enough money for gas to drive out there. i usually fill up my tank when i get paid and i work close to home, so it can last 2 weeks if i don’t have to drive to knightdale. i already agreed to let him off $125 on child support because i did not want to wait 4 months for a court date.
who usually pays for transportation in this situation?

It was spelled out in my custody agreement who picks them up and who drops them off (both me). Unfortunately, it was written when we lived 8 miles apart. Fast forward 3 years when, due to the economy, I had to move 200 miles away to find work and I still pick them up and drop them off, 19,000 miles a year worth. Without something written, I would think meeting halfway, or alternating would be fair. Child support is for the child, not for transport costs. Sorry I wasn’t more help.

Child support is for the care, feeding and housing of the child. Not driving them to and fro for his convenience. He moved, he drives. You move, you drive.