Load image in separate movie clips and repeat?

Hey guys,

I need help with actionscript.
I’m trying create a button(s) that loads 1 image in multiple (3) movie clips (SG1, SG2, SG3), one button loads one image (SG1), same button loads it in the next clip (SG2), another button loads it in last clip (SG3) and then repeats (eg. it loads it in SG1, SG2, SG3, SG1, etc…). I’m not sure how to go about this, if any one could help or give some guidance… it’ll be much appreciated!