Familiars would be detailed in the realm of greeting information, apologies if you could not find them.

Familiars differ from pets in the regard that you can use them in combat. So Philomel has a fox and a dragon that can join her in combat threads (e.g. citadel threads, please see that forum for inspiration). If you just have a pet or an NPC of importance who shows up in your storylines, then this does not need to be included when I assess and add up the power level points for your character at level one. A familiar though costs more.