Sony is putting out a call for two younger roles in Marc Webb's upcoming Spider-Man reboot.  According to Moviehole, the studio is looking for "a dark-haired Caucasian boy to play actor Peter Parker at age 4 to 6 years old", and ideally that boy should look like a younger version of Andrew Garfield, who is playing the adult Peter Parker/Spider-Man.  The studio is also casting for Billy Connors, the son of Dr. Curt Connors (aka The Lizard aka the film's villain who is being played by Rhys Ifans).  Applicants should be between the ages of 8 and 11.  I'm assuming the movie won't use this gem of a plot arc from the comics [via Wikipedia]:

The Lizard later resurfaced to face Spider-Man with the aid of a smaller twin of himself, who was revealed to be none other than his son, Billy. Curt had injected Billy with the Lizard formula while under the influence of a mysterious meteorite that caused savage behavior in those within range of its radiation. Both the Lizard and "Lizard Junior" were eventually captured and transformed back to human form, but the fact that Billy can also transform into a lizard has never been mentioned since.

The untitled Spider-Man reboot is due out in 3D on July 3, 2012.