A convertible furniture and toy assembly for children, which has a symmetrical base unit and replaceable module elements that can be attached thereto. The base unit contains two side units arranged at an equal distance from its plane of symmetry and at least two connecting elements connecting the two side units. The convertible furniture and toy assembly for children is provided with a stabilizing system in which the side unit of the base unit contains a first side element, a second side element, and an intermediate side element connecting them. The first side element is arranged at a predetermined distance X and the second side element is arranged at a predetermined distance X+Y+V from the plane of symmetry. The stabilizing system preferably also contains at least one connecting member and module elements that can be installed symmetrically on the base unit.