Srila Prabhupada writes in OT:

“The Personality of Godhead, Lord Sri Krishna, said: I instructed this imperishable science of the relationship with the Supreme to the sun-god of the name Vivasvan and Vivasvan instructed the same to his son Manu, the father of mankind, and Manu in his turn instructed the same to his son Iksvaku.”

Hayagriva gives:

“The Blessed Lord said: I instructed this imperishable science of yoga to the sun-god, Vivasvan, and Vivasvan instructed it to Manu, the father of mankind, and Manu in turn instructed it to Iksvaku.

Ref. VedaBase => Bg 4.1, 1972

and Jayadvaita:

“The Personality of Godhead, Lord Sri Krsna, said: I instructed this imperishable science of yoga to the sun-god, Vivasvan, and Vivasvan instructed it to Manu, the father of mankind, and Manu in turn instructed it to Iksvaku.”

Ref. VedaBase => Bg 4.1

Notwithstanding his dislike for the expression “the Supreme Personality of Godhead”, for which he takes the illegal freedom to change into “the Blessed Lord” Hayagriva and Jayadvaita drop the word “son” twice. Why do that? Either positive or negative, the relationship between son and father is of a very personal nature. So this a perfect example of impersonalism, which Srila Prabhupada wants to eradicate as per His second pranam mantra:

“Sanatana Gosvami and Rupa Gosvami belonged to the Bharadvaja-gotra, which indicates that they belonged either to the family or disciplic succession of Bharadvaja Muni. As members of the Krsna consciousness movement we belong to the family, or disciplic succession, of Sarasvati Gosvami, and thus we are known as Sarasvatas. Obeisances are therefore offered to the spiritual master as sarasvata-deva, or a member of the Sarasvata family (namas te sarasvate deve), whose mission is to broadcast the cult of Sri Caitanya Mahaprabhu (gaura-vani-pracarine) and to fight with impersonalists and voidists (nirvisesa-sunyavadi-pascatya-desa-tarine). This was also the occupational duty of Sanatana Gosvami, Rupa Gosvami and Anupama Gosvami.’
Ref. VedaBase => Adi 10.84