Here's my illustration of the situation:
If you have the good fortune to own any of the varied and diverse members of the Euphorbia family, do be careful, as they will seep a white liquid if cut which can be irritating to the skin and toxic if ingested.
The bottom portion of the plant got repotted in a larger container with fresh soil. The top part will be left to dry and heal over before getting his own pot or joining his mother in her new pot.
Based on how fast this plant has grown in the last year, I am hoping he will look like this soon:
|photo from here: http://onthewildslopes.tumblr.com/post/42213704895|