It is not common for a Koala to bear twins and, regrettably in this instance, the Mum was struck and killed by a passing car.  
 
Fortunately, the driver stopped and took the mother to the local vet, not knowing she was dead, where it was discovered she had twins in her pouch.

First photo: Tiny koala being fed with syringe…sooo tiny!  

Followed  by a pictorial chronology of their  growth…

Thank you for saving my life