She is near adult unless I'm seeing her wrong. How big around is she? pinky finger, index? From the photo she looks well capable of handling an adult night crawler. Here's a little scenting trick. Take one of the earth worms and cut it up in a small dish. Add a table spoon of water to the mix. Now, take the night crawler and scent the front half with the mixture. Offer it up, more then likely she'll take it. Do this a few more times and she will probably start taking them unscented. Offer some tilapia or salmon. If she takes that you can scent the worms with that also. Yes, sometimes the worms crawl back up but they usually go back when they encounter those rear facing teeth. Hope this helps.