This invention refers to a trailer, designed to transport at least one child, which can be attached to a stroller and which is equipped with a chassis with at least one wheel, a frame and an attachment assembly for securing the trailer to the stroller, and which is designed so that the trailer is connected to the frame of the stroller, is equipped with a seat, and is fitted with at least one handle, at least one foot rest and a coupling device consisting of an attachment assembly and a first and a second joint.