Just one day after International Women’s Day, Facebook CEO Mark Zuckerberg made a very personal announcement: He and wife Priscilla Chan are expecting their second child, a girl. The new baby will make their firstborn daughter, Maxima (Max), who is 15 months old, a big sister.
Zuckerberg then went on to extol the virtues of growing up with sisters, as both he and his wife did, and his gratitude and hope that his daughters will grow up with a strong sisterly bond.
“I cannot think of a greater gift than having a sister and I’m so happy Max and our new child will have each other,” Zuckerberg wrote in his Facebook post. “I grew up with three sisters and they taught me to learn from smart, strong women. They weren’t just my sisters but some of my best friends. They’ve gone on to write books, excel at performance, music, sports, cooking and their careers. They showed me how to compete and still laugh together afterwards.”
He continued: “Priscilla grew up with two sisters and they taught her the importance of family, caring for others and hard work. They supported each other as first generation college students and in their careers in medicine and business. They have so many inside jokes — the kind only siblings can understand.”
It turns out that such an idealization of sisterhood is not entirely subjective. Many objective scientific studies support the theory that growing up with one or more sisters has myriad benefits.
According to research conducted by Brigham Young University, having a sister — particularly through adolescence — protects siblings “from feeling lonely, unloved, guilty, self-conscious, and fearful.” The study showed that “it didn’t matter whether the sister was younger or older, or how far apart the siblings were age-wise.”
Researchers have also found that people who grow up with sisters tend to be “more happy and balanced” and “encourage more open communication and cohesion in families,” according to the BBC. A study detailed in LiveScience confirms that having a sister can even curb depression and guilt. Having sisters can help siblings feel more optimistic and cope with problems better, according to a study reported in the Telegraph.
Professor Tony Cassidy from Ulster University in Northern Ireland, who carried out the study mentioned in the Telegraph along with researchers from De Montfort University in Leicester, England, told the publication: “Sisters appear to encourage more open communication and cohesion in families. However, brothers seem to have the alternative effect. Emotional expression is fundamental to good psychological health, and having sisters promotes this in families.”
The study also showed that bonds between sisters in particular — as will be the case with Max Zuckerberg and her soon-to-be sis — helps the girls become more independent and ambitious. And while the Zuckerbergs seem to have a stable family life, the principle applies to all kinds of clans. “The effects were stronger among children from broken homes, suggesting that sisters might lean on each other more for support when their parents divorce,” the article said. It also suggested that boys tend to hold in emotions, while girls tend to be more expressive, holding the family together.
But why? We asked Jonathan Caspi, PhD, a professor in the department of Family and Child Studies at Montclair State University in New Jersey. The phenomenon “follows a long line of research on gender,” Caspi tells Yahoo Style. “Females tend to be more socialized, while boys tend to be more independent.” He said that girls also tend to take on more of a caretaker role in the family, making them more nurturing.
“The role of good siblings is huge, but [people] report having closer relationships with sisters than with brothers,” Caspi adds, implying that sisters tend to be the ties that bind a family. “Having a sister has all kinds of huge lifelong developmental effects. A sister can serve as a buffer for kids growing up in difficult homes [who experience] divorce, drug addiction, and domestic violence,” he adds.
But it’s not all rainbows and sunshine, of course. “Often during the early years, sisters will have differences, but as they grow most will have each other’s backs — coming to each other’s aid, feeling each other’s pain,” Susan Newman, PhD, a social psychologist, tells Yahoo Style. “Sisters can be the best of confidants, cheerleaders, and perennial comforters. Sisters have a bond, closeness, and connection that stands out as unique in family relationships … one that sisters cherish and, more often than not, rely on.”
Caspi adds, however, that sibling rivalry shouldn’t be overlooked as a very real concern among siblings — sisters included. “The No. 1 form of violence against children is from siblings. It’s under the radar,” he says. He adds that if one sister becomes the clear “favorite,” that can also sabotage the sisterly bond.
But overall, the benefits outweigh the drawbacks, and little Max Zuckerberg and her unborn sister are likely to reap similarly positive benefits to the ones their parents did from growing up with sisters. Even women who don’t have sisters seem to know that intuitively. Newman muses, “Often I hear adult women bemoan the fact that didn’t have a sister; they feel they missed the inherent, positive benefits most sisters provide.”
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