The invention relates to a child seat device (1) for a child for aligning the spinal column of the child and for preventing and treating a spinal column curvature of the child (scoliosis), comprising an upper seat part (2) and a lower seat part (3), wherein the upper seat part (2) is provided with a supporting element (8) on both sides, which supporting elements are designed and arranged relative to the upper seat part (2) in such a way that, when a child is sitting on the child seat (1), the supporting elements (8) surround the upper body of the child at the armpit level and thus limit lateral movements of the child, and wherein the child seat device (1) is part of a child car seat or stroller.
