Srimad-Bhagavatam: Canto 1 - Chapter 1 - Verse 29

Sanskrit:

ता: पुत्रमङ्कमारोप्य स्‍नेहस्‍नुतपयोधरा: ।हर्षविह्वलितात्मान: सिषिचुर्नेत्रजैर्जलै: ॥ २९ ॥

ITRANS:

tāḥ putram aṅkam āropyasneha-snuta-payodharāḥharṣa-vihvalitātmānaḥsiṣicur netrajair jalaiḥ

Translation:

The mothers, after embracing their son, sat Him on their laps. Due to pure affection, milk sprang from their breasts. They were overwhelmed with delight, and the tears from their eyes wetted the Lord.

Purport:

When Lord Kṛṣṇa was at Vṛndāvana even the cows would become moistened by affection towards Him, and He would draw milk from the nipples of every affectionate living being, so what to speak of the stepmothers who were already as good as His own mother.