The boy who played Francis at 5 (Easton Gage) also played a younger version of a Masterson brother in That '70s Show.
Playing Mozart music for babies, shown to be one of the factors that makes Malcolm smart, has since been disproven as having any effect.
When watching the entire series in a strict character back story chronology, this episode can be watched before the Pilot to see how Hal and Lois got together and ended up with 4 sons.