A video of two sisters is going viral this week, touching the hearts of people all over the world.

The video shows nine-year-old Allie and her baby sister Ashlyn, who is just 7 weeks-old. Since she is still a newborn, Ashlyn needs lots of care and attention, and Allie is only too happy to help out however she can.

When it came time for Ashlyn to go to sleep, Allie decided to help her by singing the song “Circle of Life” from The Lion King to her. She never expected little Ashlyn to react like this!

As soon as Ashlyn hears her sister’s voice, she flashes the cutest little smile! When Allie sees how her baby sister is reacting to her voice, she can’t help but burst into tears.

Their mother asks Allie why she’s crying, asking, “Is it because you love her that much?” Allie pauses a moment before saying, “Because she smiled at my sweet singing!”

She manages to regain her composure enough to keep singing, but big sister continues to have tears in her eyes. The scene is so touching that their mother starts crying off-camera as well!

It’s clear that these two sisters are going to be incredibly close for many years to come! Social media users can’t get enough of the touching video.

“How adorable is that…!! What a beautiful big sister and beautiful baby, too…!!” one social media user commented, with another adding, “Allie already knows what it’s like to be a mom… what a sweetheart! The baby is pretty cute, too!”

Check out the video for yourself below!