A collapsible child's stroller with a handle frame (30), a front wheel frame (10) and a rear wheel frame (20), mutually connected at a hinge joint (12, 22, 42) for mutual angular displacement between folded and unfolded configurations. The hinge joint has two spaced apart, parallel hinge axes, about which the frames (10, 20, 30) mutually rotate. The stroller is further provided with a locking element (43, 44) moveable between a locked position in which the frames (10, 20, 30) are locked in the unfolded configuration, and an unlocked position allowing the frames (10, 20, 30) to rotate to the folded configuration. The locking element (43, 44) moves in a direction traverse to the parallel hinge axes to better transfer loads between the frames.