They aren't forced to obey, but familiars and masters usually share an intime relation so it isn't entirely impossible for a familiar to follow the orders of their master, but not because they are compelled to but because they want to. 

So, no, there isn't anything making a familiar obey orders they don't wish to obey. 

There are familiars that may be passed down from person to person in different noble families, so they may not exactly be always in synchro with their masters.