If the bigger one has a green stripe down the middle of it's back and has bumpy skin then it is a Southern Bell Frog/Golden Bell Frog (Litoria Raniformis).
If it does not have the stripe and has smooth skin then it is a Green and Golden Bell Frog (Litoria Aurea).
The small one is a Brown Tree Frog/Whistling Tree Frog (Litoria Ewingii).
All 3 species are native to Australia and they are the only species we can keep as pets legally.