female hump smaller male

hi we are 27 hrs into the first 48hr of bonding.
dash started to hump beauty this morning, but about 2 hrs ago beauty has started to hump dash, dash is a 1/.3 smaller than beauty and they are both neutured, beauty was on 4th july 2012.
my wife is sitting in the pen trying to stop it happening is this the right thing to do ?

i hope you can help.

thanks les

I'd suggest only stopping it if it looks like one will fight, or one potentially faces injury. He will be able to run out from underneath her if he wishes with that size difference.