The 17-year-old model is due to turn the milestone age of 18 on 3 November, but it seems her big brother couldn't wait to give her his gift.
Yesterday (22 October), Kendall posted a sweet snap of a chocolate brown coloured dog sleeping in what appeared to be a car on her Instagram page.
She captioned the picture: "Happy early birthday to me!!! my new little princess! Thank you @robkardashian you're the greatest".
Kendall is known to have a huge love for all things cute and cuddly and she is frequently seen tweeting photos of and cooing over adorable animals. So we can imagine that she is over the moon with this early pressie!
Rob's birthday gesture for his younger sibling comes almost immediately after older sister Kim celebrated her 33rd birthday on Monday (21 October).
But whatever 26-year-old Rob bought for Kim, we don't think it quite compared to the gift her boyfriend Kanye West got her.
Kanye spectacularly proposed to the curvaceous reality star on Monday by hiring out an entire baseball stadium in San Francisco and having the words 'Please Marry Me' projected onto the big screen.
And of course, she said yes!
In fact, the Kardashians have made a big deal over each of their family members' birthdays this year.
In August, Kylie was treated to a lavish Alice In Wonderland-themed bash and a surprise performance from Canadian rapper Drake for her Sweet 16.
That being said, we're now pretty eager to see what Kendall has in store for her 18th. We wonder if her new puppy will be invited?!
What is the best birthday gift you have received? Let us know below, as the best comment each week wins £50!