Crying Baby Instantly Cheered Up by Katy Perry Song

It can be challenging to cheer up a crying baby, but one mom has found the secret for brightening her daughter's mood: Katy Perry!

This trending YouTube clip begins with the baby crying in the back of a car. Then, the second that Katy Perry's track "Dark Horse" begins, her expression changes from despair to "That's my jam," and she waves her arms and nods her head as the music plays.

The video is adorable and is quickly approaching 500,000 views. 

Some of the comments include one from Jackson Gabriel Chiang: "too cute, can't take it."

Addressing the baby's somewhat mature reaction, Ruben Tello says, "i can't stop laughing that's my face when i hear dark horse too."

And fan Avril Boss declares, "omg katy's power... Purrrfect"

Even Katy Perry herself chimed in on Twitter, saying that she's "available for babysitting at 10 dollars an hour and 4 oreos."

This reminds us of the video of a boy having his mood affected by a song; that time it was A Great Big World's "Say Something," featuring Christina Aguilera, and the emotional response was quite the opposite. 

For me, a good mood-lifting song is a classic '80s dance jam from Janet Jackson or something from the new Beyoncé album to get my groove on. 

Tell us in the comments below: What's the song that changes your mood instantly?