An infant playpen includes a support frame including a pivot connection, and an enclosure installable on the support frame, the enclosure comprising a flexible material including an expandable portion having multiple folds, the expandable portion covering the pivot connection when the enclosure is installed on the support frame. In some embodiments, the enclosure may have a sidewall including an inner layer and an outer layer, the support frame extending through a hollow interior between the inner layer and the outer layer when the enclosure is installed on the support frame.