around the 18 months age i would have tried a dig yes , but im guessing if she stays at the height , she isnt going to make a * digging* dog ,
dont need size in a good dog mate
a mate of mine on here uses 2 jack russels ones 10" tts and the other is 11" if im right i know they are smaller than mine. and they are very capable dogs , never failed yet so dont be put off by the size.