A combination bottle and system for devising combination bottles for the retention of liquids and other pliable items is provided. A base container unit with an open mouth is configured to retain liquids and exhibits a base unit perimeter lip with an attachment configuration and the base container unit may be combined with various capacity adding units which have perimeter lips with a variety of attachment configurations that allow attachment between the base unit and the capacity-adding unit(s). The base container unit may be combined either alone or with various numbers of capacity adding units with one or more top units that have top unit perimeter lips with top unit attachment configurations mateable with the various constituent members of the combination bottle system. Various top units are provided which exhibit functional end selected from the group of: sippy cup functional end, straw functional end, and nipple functional end. By varying the size of perimeter lips and projection aspect, necks may be cr
