Kourtney gave birth to her little girl in front of the cameras for Keeping Up With The Kardashians in July 2012 and we can't believe how grown up she is already looking!
On her birthday, the family were quick to send the toddler their best wishes and her grandmother Kris Jenner paid a touching tribute to the tot on Instagram.
She said: "Happy Birthday to my beautiful little angel princess Grandaughter Penelope!!!!!
"You are our little ray of sunshine and brighten every day....I love you sooooo much!!!! #blessed #lovebunny #family #birthdaygirl."
Meanwhile, Penelope's proud aunt Khloe has also posted her own picture on Instagram, which shows the star cuddling and puckering up to her niece.
Commenting on the cute snap, Khloe simply said: "Birthday princess."
Last month, Kourtney's sister Kim and her husband Kanye West threw an entire 'Kidcella' festival to mark daughter North's first birthday, however it seems nothing quite so mega has been planned for Penelope.
Currently, Kourtney is in New York filming new show Kourtney and Khloe Take The Hamptons and was snapped with Penelope cuddling into her pregnant tummy earlier this week.
Kourtney is expecting her third child with Scott.
Celebrities who have announced pregnancies in 2014:
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