Srimad Bhagavatam Canto 04, Chapter 08, Text 11

SB 4.8.11

na vatsa nrpater dhisnyam
bhavan arodhum arhati
na grhito maya yat tvam
kuksav api nrpatmajah
 
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
 
Queen Suruci told Dhruva Maharaja: My dear child, you do not deserve to sit on the throne or on the lap of the King. Surely you are also the son of the King, but because you did not take your birth from my womb, you are not qualified to sit on your father’s lap.
 
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
 
Queen Suruci very proudly informed Dhruva Maharaja that to be the King’s son was not the qualification for sitting on the lap or throne of the King. Rather, this privilege was dependent on one’s having taken birth from her womb. In other words, she indirectly informed Dhruva Maharaja that although he happened to be born of the King, he was considered an illegitimate son because of his birth from the womb of the other queen.
Srimad Bhagavatam Canto 04, Chapter 08, Text 10
Srimad Bhagavatam Canto 04, Chapter 08, Text 12