They are reportedly suing the company that owns the truck, not the driver, who has not been charged.
The driver told police the road was wet on Friday, Aug. 5 when she lost control and went right over the overpass onto the feeder near Woodforest.
The truck hit a car that had four people in it. Three of them were able to evacuate the vehicle, but 22-month-old Nicholas Resendiz died.
The lawsuit says the money will cover medical bills, and other damages.