Toddlers at just 15 months old are able to adjust their behavior if they notice a caregiver is angry, according to new research reported by the Daily Mail.

For the first time, it's demonstrated that children pick up on many emotional and visible cues to tell how others are feeling. Scientists were surprised to learn that children may be able to do this even if they don't know how to talk yet.

These young children can also detect anger when observing social situations and then use that information to alter the way they act, researchers at the University of Washington found. The breakthrough study will be published in the newest issue of the journal Cognitive Development. 

The study also showed a link between toddlers' likelihood to ignore people's anger and their impulsivity,  according to i09. Parents may be able to use this study to start guiding children at a younger age if it's shown that they are less inclined to follow rules.

"Self-control ranks as one of the single most important skills that children acquire in the first three years of life,"  co-author Andrew Meltzoff told the Daily Mail.

A mix of 150 boys and girls aged 15 months sat on their parents' laps while they watched a researcher demonstrate how to use an array of toys. Pieces of the toys moved and made sounds, like plastic beads that rattled inside a cup and a wooden stick that could made a small box buzz. According to the researchers, the children were intrigued and leaned over the table to learn more.

Another researcher then came in the room and complained in an angry voice when the toys were being demonstrated. They used words like "aggravating" and "annoying" to describe their feelings about what was happening.

If the emotional researcher turned their back or left the room, the children would pick up the toys and mimic what the demonstrator had done. If the emotional researcher watched the child or looked at a magazine with a neutral facial expression, the children would hesitate for up to four seconds on average before reaching for a toy. They were also less likely to mimic what the demonstrator had shown them.

The test didn't take into account a child's particular home environment or how different parents react to emotional situations. But parents were asked to fill out a questionnaire, which showed that a child who was more impulsive would be more likely to do forbidden things when an angry adult was present.