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Help Topics > All Properties > Family
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the family property of a button is used to group buttons into a set of buttons that act in concert.For example, with a group of radio button’s only one button can be on at a time putting the buttons into the same family (and having autoHilite on) will make it so only one button is selected at a time.

Usage:

set [the] family of "button" to "number"

Example:

set the family of button 1 to 1
answer the family of button 1