Your bro should have gotten same sex robos but its too late now. Not sure you can put the females together as their are not the same age. They might end up fighting to death. I wonder if the mongolian gerbil intro trick would work with robos or not?

Anyway you have to separate the male from the male as the female will get stress and defensive towards the male in the same tank.

seems like no choice but to separate, since both females will fight.. at this point, even if u buy new robos to accompany them also quite difficult, scared they fight with the new ones..

unless u can observe that ''His'' and ''Robo'' wont mate.. cos some female robos are very choosy of their mates.. but it's a high risk to take lah.. who knows if they mate when u're not around.. so, it's up to u loh..

Well, for starters. it is not safe to place a pregnant robo with another male or female. You shouldn't place it with a male cuz he might impregnate her after she gives birth. You shouldn't place with another female because the female might go over and steal the pups. There will be a tug of war like thingy with the pups as the rope. Ends up all the pups will get eaten because the mama feels threatened and the pups don't smell like her anymore. It's important for the pups to smell like her so she can recognize her own pups. So no touchy touchy of the pups with anything when they're born.

For now you must put each robo on their own. When the pups are born, you can slowly introduce and group them in 1 "boys only" tank and another "girls only" tank. Kelantan style I guess.