Is there a commandment to love your parents?

In Exodus 20:12 or Deuteronomy 5:16 (i.e. in the ten commandments), it states that you should honour your father and mother. I have often heard that we are commanded to love our parents: is this just folk-religion? Is there a Biblical commandment to love your parents? Is this just loving your parents as part of loving your neighbour (e.g. Mark 12:31)? Or is there a specific commandment?