Canto 2 -
Ayodhyā-kāṇḍa
Chapter 26: Rāma Meets Sītā and Instructs Her
Text 2.26.37

औरसानपि पुत्रान्हि त्यजन्त्यहितकारिणः।
समर्थान्सम्प्रगृह्णन्ति जनानपि नराधिपाः॥

aurasān api putrān hi tyajanty ahitakāriṇaḥ
samarthān sampragṛhṇanti janān api narādhipāḥ

aurasān = their own; api = even; putrān hi = sons [incapable of serving their purposes]; tyajanti = abandon; ahitakāriṇaḥ = of evil deeds; samarthān = [ordinary but] capable; sampragṛhṇanti = and fully accept; janān = people who are not their relatives; api = even; nara-adhipāḥ = kings.

Kings of evil deeds even abandon their own sons [incapable of serving their purposes] and fully accept even [ordinary but] capable people who are not their relatives.1

1 “Own sons” here refers to biological sons.