Identical words can be used to describe a mother and a father, but those words do not retain a consistent definition: They are translated to reflect parenting stereotypes. A mother and a father might be depicted as "very involved," but most people have gendered expectations about what "very involved" means, and it has little do with time spent with children or responsibilities assumed for them. There were instances in which, despite engaging in the same behaviors, a mother who said "she could do more" and a father who said "he did a lot" were judged differently.

"I get undue adulation all of the time for simply being out with my kid," said Adam Mansbach, author of the bestselling book Go the F**k to Sleep. "Just because my kid isn't freezing to death, I'm a great father." During the height of the book's success, he was treated like an exemplary primary caretaker. In reality, he only experienced the frustratingly long bedtimes he wrote about 25 percent of the time. When he pointed this out, it was generally ignored.

"The 'goodness' or 'badness' of parenting wasn't judged on the actual objective behavioral evidence, but on how the behavior compared other judgment standards, and that judgment standard is different for men and women," said Kobrynowicz.

If the phenomenon Kruse experiences can be understood through the theory of shifting standards, his parenting is considered extraordinary because it is performed by a man. If his behavior were judged against what society expects from mothers, it becomes far less remarkable, if not entirely invisible. While politicians publicly applaud the "most important job in the world" during elections, a working mother tending to restless children while attempting to shop for groceries at the same time is unlikely to garner a second glance.

"Micro expectations add up over time," said Janet Jakobsen, director of the Barnard Center for Research on Women. "There's a convincing body of research that shows people can perpetuate discriminatory effects without intending to."

That is not to say that men who share parental responsibilities should be ignored, or that this behavior necessarily precludes praise, but how to do so is an issue that needs greater attention and discussion. The way people react to these situations could be beneficial to greater goals of gender equity, but also hold the potential to thwart those very efforts.

"We socialize each other into practice," said Kendall King, a linguist and professor of second languages and cultures at the University of Minnesota.

Consider the way adults speak to little girls. In the past decade, sociological research has made it increasingly common for parents to actively avoid calling their daughters "pretty," and to object to other traditional gender-specific praise, such as, "Aren't you a little doll!" These are seemingly positive words, but they can also serve as self-fulfilling prophecies. If little girls receive such praise, and they see their brothers being told they are "smart" or "strong," they will assume they should live up to that societal expectation.