How do I randomly pick a sprite and spawn another obj?

How can I randomly pick a blank sprite and spawn another object? I have 8 or so placed on the layout and I want to system to only pick one sprite location and spawn another object.

I think I first have to pick a random number and have it associated with the blank sprite 1-8, and then have that sprite spawn another object?

Thanks for the help,

John

The "pick random instance" event in the system object. If they are different sprites, put them all in 1 family and pick from that family.