How to report junk cars sitting on someone’s property ?

For context, my brother keeps buying junk cars and leaving them at my parents house in hopes of “fixing the car” and selling it. He bought a car in 2016 and it is sitting in the exact same spot in my parents driveway. He has his old car that is no longer working parked in front of the house as well. Just last year he bought another vehicle and guess where it’s being parked? In front of the house.

How can I report these vehicles anonymously to the city of Houston? I would hate for my parents to find out that I called and reported them for having junk cars. I’ve shared how I feel about them keeping 20 cars in their driveway and they just don’t seem to care.

So I would like to take action for them since they keep enabling my brother to bring these junky old vehicles to their home.

No HOA.