Board Thread:Theories and Speculation/@comment-45954771-20200531061256/@comment-34975992-20200727104220

Ninja Of War wrote: How would Toneri even know about the Jougan though? Hamura's moon branch family had no contact with the main Otsutsuki clan.

It seems to me that the Jougan is Boruto's inborn Otsutsuki skill. And Toneri somehow figured that out beforehand. I hope it's a completely different dojutsu and not just another amalgamation of the Sharingan/rinnegan.

Maybe it was a parting gift from Toneri unbeknownst to Naruto and Hinata after the Moon assault, only to be manifested in their firstborn (Boruto). Most probably it was also the reason why he is constantly watching over Boruto.