Sibling rivalry is an age-old story and it is heartwarming to witness a close bond between siblings – especially from day one.

An Instagram video from the Hollister family (@the_hollisterfam) has gone viral for capturing such an unforgettable moment. It shows the adorable reaction of Brittany Hollister’s eldest daughter when she meets her newborn little sister Zoe for the first time.

Hollister, 34, spoke with Newsweek about the experience that touched her emotionally.

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In the video, the little girl looked at newborn Zoe in amazement. “She came out?” she said.

“This is Zoe,” Brittany replied. The little girl, admiring her new sibling, continued, “She’s a real baby… she’s so tiny.”

Hollister said Newsweek about the meaning of this moment for her family and why she started crying in the video.

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“Our oldest daughter has a strong personality and we knew she would react strongly – we just didn’t know which way it would go,” she said. “Seeing her so curious and soft-spoken was one of the reasons I got so emotional.”

Not only did the video capture the tender moment between siblings, but it also resonated with viewers online, with many sharing similar experiences in the comments, with some recalling their own experiences of meeting a sibling for the first time.

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“I was seven when my little brother was born and I remember crying with joy with my dad. I was so touched, what a sweet big sister,” said one viewer.

Others found the video healing and thought about more difficult sibling introductions. “My son was 20 months old when we introduced him to his new little brother and it was so heartbreaking when he started crying and getting sad and walking out of the room. It took him a few months to adjust,” another person wrote. “Their bond is getting stronger as they get older. Their daughter is the sweetest and has the sweetest voice.”

A third commenter could immediately identify with the Hollisters: “We have a video of (our daughter) walking down the hospital hallway yelling, ‘Little brother, where are you?’ A year later, she still has a huge crush on him and he is obsessed with her.”

Now Brittany and her husband Grant are watching the bond between their daughters grow deeper as they begin to grow up together.

“Our youngest is now two and our oldest is four. They love their company,” Brittany said. “It’s been wonderful to see them bond as sisters and build a lasting friendship. They love watching this video of them meeting for the first time.”