Being insulted by sharp words spoken by the co-wife of the king, even in his presence, Prince Dhruva, though only a boy, took to severe penances in the forest. And the Lord, being satisfied by his prayer, awarded him the Dhruva planet, which is worshiped by great sages, both upward and downward.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
विद्धः सपत्न्युदितपत्रिभिरन्ति राज्ञो बालोऽपि सन्नुपगतस्तपसे वनानि । तस्मा अदाद्ध्रुवगतिं गृणते प्रसन्नो दिव्याः स्तुवन्ति मुनयो यदुपर्यधस्तात्
viddhaḥ sapatnyuditapatribhiranti rājño bālo'pi sannupagatastapase vanāni | tasmā adāddhruvagatiṃ gṛṇate prasanno divyāḥ stuvanti munayo yaduparyadhastāt
SB 2.7.8