I'll start.
Goldfish's best friend/s: Pepper'Bounce (Mate) [ @Fritter ] Shellwhisker [ @Shellwhisker ]

She's got an interesting relationship with Cobwebpaw and Minkpaw, as well!

Silentraven’s Hootflicker (MATE) [ Owned by @Kieran. ]
Hootflicker absolutely loves Silentraven despite her anxiety and I adore that he loves her for who she is, not for who she isn’t <3
Dandeliontuft’s Garlicfeather (CRUSH) [ Owned by @Fritter ]
Garlicfeather is the closest thing that Dandelion has to a best friend she has after the exile of her sister, Goldenberry.
Goldenberry’s Flickerflame (CRUSH) [ Owned by @Starphobia ]
Since Goldenberry’s exile, she’s been a nervous wreck, but despite him leaving her when they went to Riverclan camp, she loves him with a heart of gold!
Butterflywings (Butter’s) Coyotekit (Pretty much her kit) [ Owned by @Fawnheart<3 ]
THEY ARE JUST SO DAMN CUTE TOGETHERRRR!! * Me still dying reading their bonding rp posts *
Butterflykit’s Mousekit (FRIEND) [ Owned by @TheRadioDemon ]
Despite only just meeting I think they’re meant to be friends <3
Fallentree’s Snakewhisker (CRUSH) [ Owned by @/Fawnheart<3 ]
Snakewhisker is this cat whom doesn’t seem fazed by Fallentree’s terrible speaking skills and Fallentree just loves it <3
Daisyflight’s Springpaw (APPRENTICE) [ Owned by @Naila ]
Springpaw is like a daughter to Daisy <3
Cloudnose’s Silverstorm (CRUSH) [ Owned by @Desert Rain Frog ]
Silverstorm is an amazing friend to Cloudnose and even went to help him when he was attacked and blinded <3
( I have way too many )