And when 7 On Your Side took the box to a lab to be tested, what we found was disturbing, but not uncommon.
2-year old Rahman Dawodoo loves his juice boxes.
His parents only buy the brands with less sugar and 'real' fruit and vegetable juice inside.
But last month say they found something else in his box.
Shortly after Rahman drank the juice, he started throwing up.
Rahman Sr. says he ripped the juice box open to have a look and saw a mushy object floating around.
Dad rushed his son to the emergency room, and the toddler was put on two antibiotics.
His dad's only desire: to find out what the object is and how it got in his son's juice.
The dad says the juice box was newly purchased, in a plastic wrapped 8 pack from the grocery around the corner. It expires in February of next year.
Asked what he thinks it is, Rahman said 'Maybe animal intestine. But I hope it's fruit."
It turns out it's not a dead animal or plant but it is alive.
"The outgrowth of a mold inside this product," said Ron Schnitzer, the director of Sani-Pure Labs.
Schnitzer analyzed the sample for us, concluding it's common airborne mold.
"Trust me, on a daily basis you are handling raw foods a lot more serious than this," said Schnitzer.
He thinks the package was damaged, even by the tiniest tear allowing air to get in.
"Small enough that you didn't notice product leaking out but air can get in and if air can get in mold can get in," Schnitzer said.
From a microscopic spore, it grew, living off the nutrients in the juice, until little Rahman's run in with it.
The juice box manufacturers say this problem is rare, but does happen. And they caution each parent test any juice box for leaks before drinking.
You should squeeze it and see if the liquid it shoots out is compromised in some way, maybe in the delivery or in the store, on maybe even in your shelves.
Apple and Eve also told us it will pay any of Rahman's medical expenses.
"I was so glad I called 7 on my side and they were able to look out what the cause may be," said Rahman, Sr.