Zeke Walters had a snooze in the grotto queue and when it was his turn, Santa asked Zeke's parents not to wake him.
Instead, he posed for an adorable photo with the little one, that has now been viewed more than 22 million times on social media.
"I can't believe how adorable our son's pictures with Santa came out," wrote dad Donnie Walters from Indiana when posting the photos on Facebook.
Walters said he and his wife thought about leaving the line and coming back when their son was awake, but were glad when the man in the red coat advised them otherwise.
"He said 'keep him asleep' so we did and he sat in the chair and told [my wife] where to lay him," Walters told The Huffington Post.
Little did the dad realise that photo was going to go viral, admitting he has been getting messages from "all over the place".
Walters' original Facebook post of the sleepy Santa photos has been shared nearly 200,000 times and has been posted on Reddit, Imgur and other media outlets.
Walters added: "Of the 22 million views and the numerous amount of comments, there hasn’t been anything negative said.
"Everybody is just so sweet and so kind and saying how it’s their favourite picture."
One person commented on the photo: "Don't ever lose the original photo, this story may go on for many generations. The picture alone is the best I've ever seen, and I'm in my late 70s!"
Walters decided to take his son back to the shopping centre they originally attended to get an awake photo with Santa.
Unfortunately, tiredness got the better of baby Zeke once again.
"Zeke wanted to let Santa know their pictures have gone viral," wrote Walters.
"Don't you know he was asleep again. So mummy and daddy told Santa the news."