In the Egyptian pantheon there are deities who appear in the form of a child and function as a child-member of a divine family. These child deities play many important roles and form a unique class in ancient Egyptian religious thought. There are two role models who serve as a basis for unique features of child deities. The sun-child provides the basis for the concept of child deity reflecting the ancient Egyptian notion of the sun’s life-cycle. The Horus child represents a generational transition from father to son as the faithful son and legitimate heir. As the ultimate role model for other child deities, the Horus child was syncretized and identified with other major child deities, such as Ihy, Khonsu, and Nefertem, in the Late Period. Furthermore, child deities’ union with the divine parents during the New Kingdom linked them closely with the concept of the divine birth of the king, a phenomenon that may explain the growing popularity and importance of child deities in the Ptolemaic and Roman periods. Through case studies of three major child deities, namely Ihy, Khonsu and Nefertem, it has become clear that these gods experienced different paths of evolution and had different sources of power but simultaneously shared certain common traits and functions. First, they all functioned as divine intermediaries between the divine sphere and the human world, since child deities were friendlier and more accessible members of the triad. Their roles as a divine intermediary included being a divine guide, protector, and propitiator for the deceased and the living. More importantly, they can be viewed as gods of light who guaranteed the eternal renewal of the cosmos and the royal succession. In this regard, it can be concluded that the three child deities follow the pattern of the sun-child, rather than that of the Horus child, considering factors such as the superficial relationship with their parents; the absence of a dramatic childhood; and the lack of evidence for the generational transmission.