Khloe Kardashian also made an appearance, as she arrived with daughter True, six, and son Tatum, one, in tow.
The show of support for Saint comes a day after Kim treated daughter North, 10, to the Los Angeles Sparks opening game in Long Beach, California.
Kim also recently shared a clip of Saint making a buzzer beater to win a basketball game.
In addition to North and Saint, Kim and Kanye also share six-year-old daughter Chicago and five-year-old son Psalm.
Kim surprised audiences last week with an unexpected appearance on Netflix’s star-studded event, The Roast of Tom Brady, where she took the mic to deliver a tribute to the NFL icon.
Upon stepping onto the stage at Los Angeles’ Kia Forum, the SKIMS mogul faced a chorus of boos from the thousands in attendance, a moment later edited out of the broadcast.
Undeterred, Kim confidently delivered her prepared Brady-centric jokes, managing to elicit a few laughs as she wrapped up her segment.
Comedian Andrew Schulz, a fellow participant in the roast, likened Kim to a ‘robot with no human aspect’ as he marveled at how ‘unfazed’ she was by the crowd’s reaction.
‘I’ve never seen anything like that. Completely unaffected,’ he told his co-hosts.
‘Even when she was up there, they were kind of booing her. It didn’t make her smile. It didn’t make her sad. It was nothing.’
It comes after Kim looked like she couldn’t breathe in her custom Maison Margiela by John Galliano look for the Met Gala on Monday – featuring a corset that showed off her shockingly tiny waist.
Kim was seen struggling to breathe in the corset in a video shared by Vogue as she prepped for the event.