tasam -- of the little birds; patatraih -- by the wings; su-sparsaih -- gentle to the touch; kujitaih -- their chirping; mugdha -- attractive; ceshtitaih -- by the activities; pratyudgamaih -- by their efforts to fly by eagerly jumping up; adinanam -- of the happy (children); pitarau -- the parents; mudam apatuh -- became joyful.

The parent birds became very joyful by observing the soft wings of their children, their chirping, their lovely innocent movements around the nest and their attempts to jump up and fly. Seeing their children happy, the parents were also happy.