From the very beginning of his childhood, when he could not even speak properly, Śiśupāla, the most sinful son of Damaghoṣa, began blaspheming the Lord, and he continued to be envious of Śrī Kṛṣṇa until death. Similarly, his brother Dantavakra continued the same habits.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
शपतोरसकृद्विष्णुं यद्ब्रह्म परमव्ययम् । श्वित्रो न जातो जिह्वायां नान्धं विविशतुस्तमः
śapatorasakṛdviṣṇuṃ yadbrahma paramavyayam | śvitro na jāto jihvāyāṃ nāndhaṃ viviśatustamaḥ
SB 7.1.18