Watch this baby have the BEST reaction to a Katy Perry song

She really loves this song...

We're sure there are some people out there who would say that Katy Perry songs make them want to blubber but for this little girl, it's a sure-fire way to dry her tears.

And get her dancing with the most adorably weird facial expressions.

While it probably won't work for every baby, it might be worth trawling through Katy's back catalogue in case there's a track that has a similiar magic effect on your crying child.