Bloomberg Politics captured the throw and sent it out shortly before Rubio took to the Des Moines Register's Soapbox.
The kid, according to Bloomberg, is okay.
Rubio later tweeted "The QB always gets the blame," along with an ESPN article about the incident.
The Rubio campaign also added a new item to their campaign store: "Team Marco throwback t-shirts in time for football season."
But Jack Whitver says fear not - his 4-year-old nephew has been practicing for next time.
"After the now famous dropped pass, my 4yr old nephew has been practicing. He says he's ready for @marcorubio," Whitver tweeted, including a video of his nephew, on Wednesday.