SB 10.82.34
krsna-ramau parisvajya
pitarav abhivadya ca
na kiñcanocatuh premna
sasru-kanthau kurudvaha
Translation:
O hero of the Kurus, Krsna and Balarama embraced Their foster parents and bowed down to them, but Their throats were so choked up with tears of love that the two Lords could say nothing.
Purport:
After a long separation, a respectful child should first offer obeisances to his parents. Nanda and Yasoda gave their sons no opportunity for this, however, for as soon as they saw Them they embraced Them. Only then could Krsna and Balarama offer Their proper respects.