HANGING ON
I think their nest has been destroyed during a storm
I think that the mother is only thinking about making sure her children are safe.
I think the baby possum on her back, near her head, is most safe as it is least likely to fall off, unlike the babies hanging of the side.
I think we use our sense of sight the most as humans need sight to find where they are going, see what they are doing , cook, clean and many other things, whereas some animals (bats, worms ect) use their hearing and touch.