^^ This ship is as "canon" as anything in Love Live. They constantly made little wink-wink allusions to it like this. Nobody in the anime actually got together. Rin and Hanayo's little cuddle scene in the movie was nothing more definitive than Nico getting jealous over Tsubasa sitting too close to Maki.
The SIP childhood friends — RinPana and HonoKotoUmi — are omitted, but so are a lot of the Sunshine ones: no DiaKananMari, to start. Kanan arguably counts also as Chika's and You's childhood friend, and whether Yoshiko or Ruby or both are Hanamaru's childhood friend(s) seems to vary by continuity.
Which is to say you gotta draw the couplings you wanna. And all these are very cute.