Khloe Kardashian took to social media to celebrate her sister on her 42nd birthday.

She celebrates her sisters year after year with her loving notes, and this year was no different.

The star posted a slew of throwback pictures of both of them as kids and as teens and adults on various occasions.

She wished Kim a happy birthday and called her a brave and resilient person.

She said the mogul was more loving, self-aware, and patient and used to giving her absolute best.

The matriarch of the Kardashian clan also hopped online to wish her second daughter a happy birthday.

She praised the mother-of-four for handling everything with grace.

The businesswoman called her a fantastic and beautiful person inside and out.

Kim also wished Khloe a happy birthday and said she was her number one 'ride or die.’