Atri had Soma for his son and Soma's son was called Buddha. Buddha's son was Pururava whose effulgence was like that of the great Indra.
अत्रेः पुत्रोऽभवत् सोमः सोमस्य तुबुधः स्मृतः। बुधस्यैको महेन्द्राभः पुत्र आसीत् पुरूरवाः॥