Kim Kardashian penned a heartfelt birthday note for her son Saint on his 8th birthday, who she shares with ex Kanye West.

Taking to her Instagram account on Tuesday, Kim posted a series of photos, which she captured with son Saint.

 The first picture showed Kim and Saint striking pouting for the camera, while the second and third featured him sporting football jerseys of Ronaldo and James.

The series also included the playful videos, capturing Saint joyfully kissing his mom and sharing big laughs.

 Among the snapshots, there was a childhood picture of Saint and a selfie of the duo seated courtside at the latest NBA game, which they both attended on the same day.

The reality TV star captioned the post, "My twin Sainto! How are you 8 years old already! I just love you so so so much!."

In addition to this, the other members of the Kardashian-Jenner family, from Kris Jenner to Khloe Kardashian, also flooded social media with love for Kim's son.

Kris Jenner  sent warm birthday wishes to her grandson Saint in  an Instagram post.

Alongside a series of photos with Saint, Kris wrote, "Happy birthday our amazing Sainty!!!!! Your smile and your spirit and your heart just keep getting bigger and bigger! I love watching you grow up and play soccer and basketball and thrive at school and be the best brother to all your siblings and the best son, cousin, nephew, grandson and friend!!!."

"You have an infectious laugh,adorable smile, and give the best hugs in the entire world!!!! I love you sooooooo much !!!! Love, Lovey @kimkardashian," she added.

Kim Kardashian welcomed her son Saint with ex-husband Kanye West on December 5, 2015.