Corona police said investigators learned of the incident, which happened last week, through social media.
The couple behind the stunt are 45-year-old Holly Piazza and 37-year-old Brian Chase.
The two posted the video, titled "Driving a truck full of Orbeez," to the YouTube channel, RoccoPiazzaVlogs.
The video shows the couple's son Rocco and his nanny sloshing around in a truck bed full of Orbeez as they drive around Corona.
Orbeez are gel type beads that absorb water and swell up to 300 times their size.
The pickup went all around the streets of Corona, and that's the part that got them into hot water with police.
Rocco and his nanny were unsecured in the back of the truck, which is dangerous. Also, police said some of the beads were dumped onto the streets, where a lot of it later went down storm drains.
The two were arrested and cited for misdemeanor child endangerment, but they were not sent to jail. In addition, Piazza was issued a ticket for dumping the slippery beads onto the street. Police say they'll also be charged for the cleanup.
Rocco said he thought the video to go viral, but he did not expect all the extra attention from the police and the media.
"It's kind of crazy at this point right now, but it's really fun to see all this stuff," Rocco said.
If you have any further information about this case, you're urged to contact Officer Clark Eveland at (951) 817- 5764.