This one comes from Jeff Major in Oklahoma:
"I also remember the episode in which Astro Boy got his little sister -- Astro Girl -- in a beautifully-wrapped box for his birthday (which was after Dr. Elefun gave him his parents in a similar box). The entire episode showed how he was responsible for "socializing" his little sister, who was not a very apt pupil. She had more fun snapping off stop signs and dancing with them than obeying her brother! She then went to a robot wrestling match and beat up another robot 10 times her size. She was discovered by a robot scientist who was testing cloning techniques and wanted a robot subject to see what would happen. Out of curiosity, she submitted to his experiment and when she went home she kept splitting down the middle, grasping both sides of her head and shoving the halves back together! Her robot mother said, "If you have a headache, then you'll have to go to bed." In her bedroom, AstroGirl was afraid of getting spanked for what she had done. Before she could do anything else, she halved again but the other half of her jumped across the room. There was an eerie whine as both halves filled in their empty sides, and suddenly there were two identical Astro Girls. One stays at home, the other goes to the robot wrestling arena without telling anyone. Before the robot scientist realizes what he has done, she re-enters the competition -- and is destroyed by the competing robot because she only had half of her strength. The other Astro Girl comes to the arena and cries over her dead twin, and Dr. Elefun and the other scientist conspire to restore the remaining twin -- which they are able to do."
Thanks so much for this GREAT blow-by-blow description of an all-time classic episode!!

Even robots have siblings in the world of Astroboy
(picture courtesy of Glen Johnson)
(click on the picture to hear Tatsuo Takei's delightful theme for Astrogirl)