16. A child seat headrest comprising: a one-piece head support including a generally planar support wall, right and left spaced-apart wings integral with and extending laterally from right and left sides of the generally planar support wall, and a head-support holder integral with and extending downwardly from a bottom side of the generally planar wall; a head rest member configured between the right and left space-apart wings for pivotal movement relative to the generally planar support wall, the head rest member being pivotally movable between a rearwardly-inclined sleeping position wherein the head rest member is proximate to and substantially coplanar with the generally planar support wall, and an upright waking position wherein the head rest member is at an oblique angle relative to the generally planar support wall; and the head rest member including right and left pins extending outwardly from a lower portion of the head rest member toward the respective right and left spaced-apart wings and an intermediate portion of the one-piece head support between the generally planar support wall and the head-support holder including right and left side oblong apertures, the right and left side oblong apertures being configured to receive the right and left pins for effecting vertical and pivotal movement of the head rest member relative to the generally planar support wall.
16. A child seat headrest comprising: a one-piece head support including a generally planar support wall, right and left spaced-apart wings integral with and extending laterally from right and left sides of the generally planar support wall, and a head-support holder integral with and extending downwardly from a bottom side of the generally planar wall; a head rest member configured between the right and left space-apart wings for pivotal movement relative to the generally planar support wall, the head rest member being pivotally movable between a rearwardly-inclined sleeping position wherein the head rest member is proximate to and substantially coplanar with the generally planar support wall, and an upright waking position wherein the head rest member is at an oblique angle relative to the generally planar support wall; and the head rest member including right and left pins extending outwardly from a lower portion of the head rest member toward the respective right and left spaced-apart wings and an intermediate portion of the one-piece head support between the generally planar support wall and the head-support holder including right and left side oblong apertures, the right and left side oblong apertures being configured to receive the right and left pins for effecting vertical and pivotal movement of the head rest member relative to the generally planar support wall. 19. The child seat headrest of claim 16 wherein each of the right and left spaced-apart wings includes a slot in an upper portion facing the head rest member, the slot having a hook-in connection that defines the rearwardly-inclined sleeping position and the upright waking position.