Hello - our two girl piggies are now 4 months old, and it's becoming apparent that Machu is more dominant than Picchu. Their cage has one sleeping area under cover (Machu is much shyer and spends a lot of her time hiding out in there), and I've noticed that poor little Picchu isn't allowed in there by her sister - she gets rumbled at and scoots out pretty quickly. Is this a problem? They're in a warm room, and there's an extra play tunnel in the cage where she can hide out if she wants - should I be worried?