I think with the exception of Mark who is in all 3 subunits, Taeyong and Doyoung are the two members of NCT with the best relationships in the band. Obviously all 18 of them are friends, but they’re not all close and some of them probably go weeks without seeing each other since they’re not all in the same units/dorms. But it seems like Taeyong and Doyoung have fairly good relationships with the other 17 members. Taeyong because he’s the unofficial leader and has spent downtime getting to know all the members. And Doyoung because he’s in 127 with half the band, and is Mom #2 to NCT Dream and spends time with them. Plus he’s a part of ‘96 line with Ten and Kun.