maybe you could ask the lady if you could watch her for just a little bit longer because you plan on becoming a fosterer. when my aunt lived in australia she had many wallabies, i wonder how much they cost over here in the states. i do know that when they grow up they are very strong, much like monkies and that they can become a little more agressive, kicking and such. i know a wallabie looks little but a full grown one can knock you right over if you're not paying attention. be sure the lady knows you REALLY want this wallabie and see if she can do anything for you. ask for help, that may be the only way you will be able to keep this wallabie.