Both Sasuke and Madara's Sharingan awakened/evolved after they

Both Sasuke and Madara's Sharingan awakened/evolved after they broke their bond with their best friends. I love this parallel. : r/Naruto

Would Naruto awaken the Rinnegan if he takes the Sharingan from Sasuke? - Anime & Manga Stack Exchange

Would Naruto awaken the Rinnegan if he takes the Sharingan from Sasuke? - Anime & Manga Stack Exchange

Sasuke otsutsuki, Anime Omega Wiki

Evolution of the Sharingan and Other Eyes: Naruto Shippuuden

Why does Madara say Sasuke awakened the same pattern Rinnegan as him and then proceeds to say they share a bond more than blood when their patterns are not the same since

All Mangekyou Sharingan awakening [Indra, Madara, Obito & Kakashi, Itachi, Sasuke] Explanation !

Question for manga readers, does manga explain how exactly does eternal mongekyo sharingan works? : r/Naruto

Madara Stabs Sasuke! Gaara's Plan – Naruto 661