Yes. We learned that River knew that Amy is her mom in "The Wedding of River Song". She came to Earth in a meteor shower and had a talk with Amy. River had just come from the crash of the Byzatium (which was in "The Time of Angels"). She remarked on how young Amy had seemed to her then. She also said that she had to lie and pretend that she didn't know Amy and a few other lies that she had to tell.