Pranks are basically just a socially acceptable form of bullying that have been used by siblings to torture each other since the beginning of time. But catfishing your own sister to make a point and then humiliating her in public is not a normal sibling prank IMHO. But you can decide for yourself.
He explains that he discovered she was on Tinder when a notification popped up while he was using her phone. He asked her "why" she was on Tinder and she told him it's none of his business.
He writes:
Last week, I was using my sister Ashley’s phone because mine was dead and I needed to call a friend to confirm plans. Dialing my friend’s number, I saw a tinder notification of some dude messaging her. Immediately, I asked why she’s on tinder (she’s 17) and she grabbed her phone back and said “none of your business”