A Utah woman couldn't help but laugh after spotting her 8-month-old niece reacting to her with the sassiest of eye rolls.
In a video posted to TikTok, Aspen Mather can be seen expressing her delight at being able to hold the child without her calling for her mom.
"Guys, she's letting me hold her without crying," Mather says to the camera. "She's usually attached to her mom."
Mather then switched to a higher-pitched, childlike voice as she excitedly told the tot: "But you're letting me hold you now!"
Maybe that's what sparked the baby's reaction. The child is seen looking off at the camera and rolling her eyes, seemingly in response to Mather. In truth, the eye roll might have been missed had Mather not been trying to film a video of them together.
Laughing in disbelief at what happened, Mather says: "You guys, she just rolled her eyes!"
The video, captioned "Sassy 8-Month-Old Baby Rolls Eyes at Aunt," has been watched nearly 3 million times online.
Newsweek reached out to Mather for comment via TikTok.
What inspired the child to do this is unclear, but research would suggest it's a behavior she learned from an adult.
For decades, researchers have debated whether babies are capable of initiating adults from an early age. One of the earliest studies, published in 1983 in the journal Child Development, indicated that newborn infants were capable of imitating basic adult facial expressions like sticking out a tongue.
A more recent, longitudinal study, published in a 2016 issue of Current Biology, said that young infants produced gestures of this kind regardless of what was modeled by adults.
It could be more complicated than that, though. A research paper in the journal Infant Behavior and Development said in 2011 that babies tend to reserve imitation for people they trust.
As part of the research, 60 babies between 13 and 16 months were placed into groups. In the first group, some "unreliable" experimenters looked inside a container while expressing excitement at what was inside. They then invited the babies to look in. In these instances, the boxes were empty.
A second group repeated the task with "reliable" experimenters who reacted the same way. The difference was that when they invited the babies to look inside the box a toy was there.
For the second part of the experiment, each of the babies watched the same experimenter they had been paired with on the first task. In this instance, the experimenters were tasked with using their foreheads rather than hands to push on a light. The children were then watched to see if they did the same.
The results highlighted how 61 percent of the infants in the "reliable" regroup imitated the light switch behavior. By contrast, that figure dropped to 34 percent among those who perceived their experimenter to be less reliable.
All of which illustrates how infants tend to imitate the behavior of reliable adults.
In the context of Mather's video, you have to wonder whether her niece might have been imitating her aunt's reaction to certain stimuli or maybe even her parents'.