So I have two guinea pigs, both females just over one year old. I'm a little concerned about their activity level. After doing a fair amount of research, I've come to the conclusion that guinea pigs are generally very social, active little critters. Not mine. They sit in separate cages (due to fighting and intimidating each other away from their food) and used to run around every morning, but they've long since stopped. I try to put them in the same cage, but they end up sitting in opposite corners, not changing their behavior in any way. I set them on the floor, and they hide in a corner. I take them outside and they refuse to leave my lap. Is there any way I can promote activity, or at least more playfulness between the two? I'm worried that their laziness may affect their health.