Proving grounds level of Bioshock, glitched?

I made it to the second to last level at the end. In the level you have to escort the little sister. When I escorted her, she glitched at the wall. And it said to collect the Harvesting Tool to kill Fontaine. But, she has nothing in her hand. I re did the level a few times, and the sisters just started to stack up. The sister is now like, in the middle of the level. And it keeps saying ' grab the tool ' but theres no tool in her hands.