There were balloons, there was cake, and as you'd expect from the famously dramatic fam, there was even a tantrum or two.
Penny's mama Kourt took to Instagram to share a pic where the tiny tot was literally over it!
"Birthday mood", she captioned the hilar pic.
Because North West isn't the only famous kiddy who can throw a tanty!
Also, her ballerina outfit is #birthdaygoals!
Here are some other snaps from the (sometimes) happy occasion:
HAPPY BIRTHDAY PENNY! <333