'This Is Us' shows why brother-sister relationships are so powerful

This Is Us has developed a cult following thanks to turning heartbreaking moments into can’t-miss TV, but its narrative around the sibling relationship between Kevin, Kate, and Randall Pearson is also unique.

Tuesday’s episode (spoiler alert!) featured the Pearson siblings hitting Vegas to celebrate Kate’s upcoming marriage to her boyfriend Toby. Tensions arose when Randall received a sudden phone call from his former foster child that caused him to miss Toby’s bachelor party, a move that didn’t sit well with Kate. Making matters worse: Kate and Randall’s wife, Beth, bickered, resulting in further tension between the brother and sister. Ultimately, the sibs found common ground, with Kate declaring, “I like to pride myself that I was the first person to realize that Randall Pearson was the coolest person in the world.”

People on Twitter gushed over the happy ending.

The biological, long-lasting relationship between siblings has been proven to help model social skills, improve conflict resolution, and, depending on the quality, even stave off loneliness and depression.

And while pop culture is obsessed with the fraught nature of same-sex siblings (Frozen, Little Women, The Fighter, What’s Eating Gilbert Grape), brother-sister bonds get far less attention.

But here’s what science has discovered about these unique bonds: Growing up with a sibling of the opposite sex can give you a dating edge during your teen years, per research published in the Journal of Youth and Adolescence. The study found that these types of siblings are more confident in their ability to attract and maintain potential mates due to a life spent negotiating with a member of the opposite sex.

And according to The Spokesman-Review, one classic study found that brother-sister pairs are more open-minded about gender roles than same-sex siblings. In the study, boys with older sisters were just as likely to play house as two sisters. And in two-child families, these siblings may experience less arguing “because each one has staked out exclusive territory as the only boy or only girl in the family,” according to the magazine.

Read more from Yahoo Lifestyle:

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