Kim Kardashian is a doting aunt as she wishes Mason and Reign a happy birthday in sweet throwbacks

Kim Kardashian recently celebrated her 40th birthday on a private island.

But the Keeping Up with the Kardashians star kept it a bit more low-key when wishing some of her favorite kiddos a happy birthday.

She was a doting aunt Monday as she took to Instagram with some sweet throwback photos of herself and nephews Mason and Reign, sending her best wishes on their shared birthday.

Birthday boys: Kim Kardashian was a doting aunt Monday as she took to Instagram with some sweet throwback photos of herself and nephews Mason and Reign, sending her best wishes on their shared birthday

The 40-year-old wrote: ‘Happy Birthday Mason and Reign. Birthday twins but 5 years apart. I remember when @kourtneykardash was pregnant with Reign and it started to get close to Mason’s bday.

‘I suggested she induce so that they don’t have the same birthday but she said her famous phrase “whatever’s meant to be will be”. And her water broke the night before Mason’s bday and little Reign was born on Mason’s day! Happy Birthday to the coolest boys in the world!!!!’

She included a photo of herself holding baby Mason, who’s turning 11, and one of her giving Reign a kiss, celebrating his sixth birthday.

Sister Kourtney Kardashian, 41, shares Mason, Reign and daughter Penelope, eight, with Scott Disick, 37, whom she was with from 2006 to 2015.

Sweet memories: Kim recounted when Reign was born: 'Her water broke the night before Mason's bday and little Reign was born on Mason's day! Happy Birthday to the coolest boys in the world!!!!'

Sweet memories: Kim recounted when Reign was born: ‘Her water broke the night before Mason’s bday and little Reign was born on Mason’s day! Happy Birthday to the coolest boys in the world!!!!’

Happy family: Sister Kourtney Kardashian, 41, shares Mason, Reign and daughter Penelope, eight, with Scott Disick, 37, whom she was with from 2006 to 2015

Happy family: Sister Kourtney Kardashian, 41, shares Mason, Reign and daughter Penelope, eight, with Scott Disick, 37, whom she was with from 2006 to 2015

It comes just a week after Kim celebrated her own son Saint’s fifth birthday with a sweet Instagram tribute.

She wrote: ‘My baby Saint turns 5 today. One of my life’s soul mates. Every year I interview my kids and ask them the same exact questions about life. Saint- I can’t wait to see how you’ve grown and how you answers these questions as a 5 year old and show them to you when you’re big. 

‘I know a drive- by party isn’t ideal but it’s our times and you are so excited! You are always so joyful and bring so much joy into my soul every single day. You will always be my baby boy. Enjoy your golden bday this year Sainty! #5onthe5th!!!’

The SKIMS mogul shares sons Saint, Psalm, one, and daughters North, seven, and Chicago, two, with husband Kanye West, 43, whom she married in May of 2014.

Proud mom: It comes just a week after Kim celebrated her own son Saint's fifth birthday with a sweet Instagram tribute

Proud mom: It comes just a week after Kim celebrated her own son Saint’s fifth birthday with a sweet Instagram tribute

Mama's boy: She wrote: 'You are always so joyful and bring so much joy into my soul every single day. You will always be my baby boy. Enjoy your golden bday this year Sainty! #5onthe5th!!!'

Mama’s boy: She wrote: ‘You are always so joyful and bring so much joy into my soul every single day. You will always be my baby boy. Enjoy your golden bday this year Sainty! #5onthe5th!!!’

Big brood: The SKIMS mogul shares sons Saint, Psalm, one, and daughters North, seven, and Chicago, two, with husband Kanye West, 43, whom she married in May of 2014

Big brood: The SKIMS mogul shares sons Saint, Psalm, one, and daughters North, seven, and Chicago, two, with husband Kanye West, 43, whom she married in May of 2014

A source recently told People that the couple is still together after a turbulent year, but they ‘very much live separate lives.’

The insider added: ‘Kim has work and projects that are important to her, and Kanye has his. Their lives don’t overlap much.’

It comes after they were rumored to be heading toward divorce, amid Kanye’s bipolar episode and his bizarre last-minute presidential bid, during which he revealed at a rally that they nearly had an abortion when pregnant with North.

Kanye has been spending much of his time at his $14million Cody, Wyoming Ranch, while Kim stays busy working on her law degree and advocating for prison reform.

Separate lives: A source recently told People that the couple is still together after a turbulent year, but they 'very much live separate lives': 'Kim has work and projects that are important to her, and Kanye has his. Their lives don't overlap much' (pictured in February, 2020)

Separate lives: A source recently told People that the couple is still together after a turbulent year, but they ‘very much live separate lives’: ‘Kim has work and projects that are important to her, and Kanye has his. Their lives don’t overlap much’ (pictured in February, 2020)