Bhishma said One's own begotten son considered as his own self. The son that is begotten upon one's wife by a person whom he has invited for it, if called Niruktaja. The son that is begotten upon one's wife by somebody without his permission, is Prasritaja.
भीष्म उवाच आत्मा पुत्रश्च विज्ञेयस्तस्यानन्तराश्च यः। निरुक्तजश्च विज्ञेयः सुतः प्रसृतजस्तथा॥