Say cheese! Kim Kardashian shared an adorable photo on Instagram of all four of her kids posing together in the backyard. She captioned the sweet snap, "My whole heart." The reality star's 6-year-old daughter North looked all grown up as she put her arms around 1-year-old baby brother Psalm. Meanwhile, 4-year-old Saint happily flashed a peace sign for the camera while 2-year-old Chicago offered up a precious grin!