Abstract: A convertible bicycle trailer and jogging stroller for two children comprises a frame with a rear axle end for supporting two large diameter wheels and a front fork end removably supporting alternatively a front wheel for use in the stroller mode and a trailer cycle hitch assembly attachable to the frame portion of a cycle for use in the trailer mode. The frame has a rigid plastic molded shell which is conformed into a side-by-side two child holder seat portion with side, rear and front portions for substantially enclosing two children and being fastened to the frame. The side portions are configured as side fenders for covering upper portion of the two large wheels. A removable handle is attachable to the rear portion of the sise fenders for use in the stroller mode. The trailer and stroller combination further includes a roll bar and a protective canopy to add further protection of the children.