Sofia Richie has stepped-up her 'step-mom' duties this weekend.
RadarOnline.com has all the details – click through for more.
Scott Disick, 34, and Sofia Richie, 19, took care of his three kids this weekend while Kourtney Kardashian partied at Coachella.
The pair was spotted taking the kids Mason, Penelope and Reign, to a toy store in Malibu.
The news will be embarrassing to Kardashian, 37, who previously was unhappy that Sofia was spending more time with her kids.
A very youthful looking Sofia showed off her taut tummy in a crop top for the day with her new partner's children as she wore baggy striped pants.
Richie sported a small Louis Vuitton backpack for the outing with her hair up in a bun as she seemed happy with the kids.
Disick also looked relaxed wearing an all white outfit as he accompanied his kids.