CHUNKY KNIT JUMPER STONE Petite Co au Nature Baby Billy Jumper Bold Sunny Stripe Chunky Knit Chunky Knit Jumper Baby Pink Little and Fern CHUNKY KNIT JUMPER STONE Petite Co au. The Billy Jumper is a classic, easywearing sweater style that will keep little one comfortable all year round. Knitted in a chunky certified organic cotton yarn, this jumper is durable and easy to care for. * GOTS Certified * 100% organic cotton * chunky tuck knit stitch * knitted rib cuffs and hem