Family groups of deities became very popular in the Late Period (661-332 BC), and were placed in temples by wealthy individuals. The most important group of deities was the triad (a group of three persons) of Osiris, his wife Isis, and their son Horus. They represented the king of the dead, the divine mother, and the living king respectively, together they were the perfect family.
The myths surrounding these deities were very popular. The tale is one of murder, intrigue and revenge, appealing to both Egyptian and later Roman audiences, a version of it being written by the Greek author Plutarch. The story explains how Osiris became god of the dead, and the transmission of his rule to his son Horus, a metaphor for the divine origins of Egyptian kingship. Another element is the struggle between order, represented by the divine family, and chaos, symbolized by the god Seth, who murdered Osiris and attempted to seize power.
Isis and Horus, represented in this statuette group, were important protective deities. Isis was revered for her skills with magic, sufficient to revive Osiris for long enough to conceive a child. Horus, as Harpokrates, was given power over dangerous animals to protect him from Seth.