What does it mean when Mockingbird flies in your house?

Mockingbirds are known to repeat the songs of other birds often more loudly and in rapid succession. (Hence their name) A mockingbird in your house signifies some competitive element, most probably a competition for attention, less possibly a competition for opportunity or resourses. Most famous instances have been over competative love affairs. Shortly after her marriage, Maria Leszczyńska, wife of Louis XV if France, was surprised one morning by a pair of fighting mocking birds that flew into her bedroom. In retrospect, this was deemed to be an omen of the king's many courtesans, mistresses and love affairs.