Yes they are. Mini's are a form of Familiar. Core Rulebook page 216 reads: "An evil sorcerer who learns the right ritual may make a 'mini' as a familiar. This mini bears a strong resemblance to the sorcerer in looks and mannerisms, but is much, much shorter. These are usually named Mini-sorcerers name, such as Mini-Zzabur, though some have just called them things like Mini-Me."