Gobhilagrihyasutra 2.8.21

2.8.21

viproṣya jyeṣṭhasya putrasyo 'bhābhyāṃ pāṇibhyāṃ mūrdhānaṃ parigṛhya japed, yadā vā pitā ma iti vidyād, upetasya vā, 'ṅgād aṅgāt sambhavasī 'ti;

When (the father) returns from a journey, or when (the son) begins to know, 'This is my father,' or when (the son) has been initiated, (the father) should grasp with his two hands his son round the head, and should murmur, 'From limb by limb thou art produced' (MB. I, 5, 16-18).