What does it mean when a pigeon is following another pigeon?

It's not common for a pigeon to follow another pigeon. It's possible that one pigeon may be trying to woo another pigeon, or they may be part of a flock and are simply flying together. Alternatively, one pigeon may be looking for a mate, or the trailing bird could be a juvenile searching for its parents or flock. It could also mean that the pigeons are a mating pair and they have a connection.