How to convince my parents for another Reptile?

Hey guys.. I have a Leopard Gecko now that i had for about 2 years, hes doing great and hes healthy. I got him from someone else that couldnt care for him anymore, so i took their tank and heating and stuff and used that untiil my birthday where i got a whole bigger setup and looked so much nicer. My sister has a Betta fish, and tomorrow shes getting a Guinea Pig..-.- but my mom did say I could get a frog, but the one i researched that looked cool, he eats mice..my mom doesnt want anything that eats mice, NO snakes, NO turtles (because she apparently got "salmonella" from a wild one when she was a kid." so i dont know what to get or what to ask for..