As the oldest child, I spent the first four years of my life being the center of my parents' attention.

When my parents first told me that they were having another baby, I didn't fully comprehend what that meant for me as a big sister. So the day my brother came home was one that I will never forget. I had to adjust to sharing my parents and it was not easy.

I was jealous and envious of how much my mom and dad as well as everyone else paid attention to him. I eventually got over it, and over the years we formed an unbreakable bond.

While it took me sometime to accept having a sibling, there are some kids that embrace their new role as soon as they meet their little brother or sister. They'll even go the extra mile to show their love, and for one boy, singing to his baby sister was how he went about it.

A mother was lucky enough to catch her son and daughter sharing the cutest moment ever, so she made sure to film it and share her joy with the rest of the world. The video has since amassed millions of views and it's not hard to see why.

In the video, the boy is holding his sister on his lap as he sings to her the sweetest song. Instead of opting for a nursery rhyme like most kids his age would, this big brother gazes into his sister's eyes and starts to serenade her with Joe Crocker's 1975 hit "You Are So Beautiful."

He even cradles her face as he sings, and clearly, he's doing a great job because the little girl appears to be enjoying the tune.

"Aww, she smiled!" he says at the end of the song, and then gives her kisses on the forehead. It's unbelievably cute!

Unlike my mother and father all those years ago, the parents of this brother-sister pair can sleep peacefully knowing how much their firstborn loves his new sister.

Hopefully, this bond only gets stronger as they grow up. While a lot of siblings bicker and fight, it's clear that these two will be grow up to be different. If he keeps on being this sweet, then this girl is really lucky to have him in her life because he will, without a doubt, always have her back.

Are you close with your sibling?