Carrie Underwood Shares the Sweetest Tour Bus Photo of Baby Isaiah

Shortly before performing for a massive crowd at Washington state's Watershed Festival on Sunday, Carrie Underwood took to Instagram to share a photo of her favorite audience: her husband, Mike Fisher, and their 4-month-old son, Isaiah. In the snapshot, captioned, "My boys . . . checking out the world through the bus window," Mike places a protective hand on his son as they share a cute moment together.

This isn't the first time the world has gotten a glimpse of the family's adorable life on the road. In May, Mike shared a ridiculously cute selfie with Isaiah on Instagram. And Carrie, who showed off her postbaby body at the CMT Awards in June, also shared a photo of the father-son duo taking a nap together during one of her dress rehearsals. See Carrie take the stage below, then look back at her 10 years in the country spotlight.