An orthopedic baby seat comprising: a relatively inflexible base , with a triangular planar cushion comprising a resiliently flexible support material, wherein the base with cushion tapers toward a front end of the base to provide a fish-tail shaped planar configuration, wherein the base with cushion is dimensioned and configured to receive and support a baby's bottom thereon; a back support , extending upwardly from and at least partially around the base in a substantially C-formation to a height of at least to the bottom of the baby's ribcage, with an opening of the C-formation directed towards the front end of the seat, wherein the back support comprises at least one layer of at least a partially flexible sheet material having a number of spaced, upwardly extending retaining formations , and a number of elongated battens , retained by the retaining formations and extending longitudinally upwardly from the base; wherein the back support provides a substantially rigid, vertical, and flexible lateral support to the baby occupying the seat; two opposing leg openings , extending outwardly from the base; and two opposed, cushioned thigh support formations , separating the base from the two leg openings, dimensioned and configured to allow hips of the baby to fall and spread naturally apart to the side, with thighs of the baby at least partially supported towards knee joints of the baby with hips and knees bent, allowing legs of the baby to spread outwardly in a supported manner while moving relatively freely in the seat. a relatively inflexible base , with a triangular planar cushion comprising a resiliently flexible support material, wherein the base with cushion tapers toward a front end of the base to provide a fish-tail shaped planar configuration, wherein the base with cushion is dimensioned and configured to receive and support a baby's bottom thereon; a back support , extending upwardly from and at least partially around the base in a substantially C-formation to a height of at least to the bottom of the baby's ribcage, with an opening of the C-formation directed towards the front end of the seat, wherein the back support comprises at least one layer of at least a partially flexible sheet material having a number of spaced, upwardly extending retaining formations , and a number of elongated battens , retained by the retaining formations and extending longitudinally upwardly from the base; at least one layer of at least a partially flexible sheet material having a number of spaced, upwardly extending retaining formations , and a number of elongated battens , retained by the retaining formations and extending longitudinally upwardly from the base; wherein the back support provides a substantially rigid, vertical, and flexible lateral support to the baby occupying the seat; two opposing leg openings , extending outwardly from the base; and two opposed, cushioned thigh support formations , separating the base from the two leg openings, dimensioned and configured to allow hips of the baby to fall and spread naturally apart to the side, with thighs of the baby at least partially supported towards knee joints of the baby with hips and knees bent, allowing legs of the baby to spread outwardly in a supported manner while moving relatively freely in the seat. <EOS>