I love these questions because I can make mama very happy very quickly!
You've hit the magical 12 week mark where there REM/non-REM sleep changes. That change means they enter a light sleep phase at the 30-45 minute mark, and that causes them to wake up. Since this is different from how they used to sleep, they don't realize they are supposed to go BACK to sleep -- that they are merely transitioning between sleep phases.
Your job is to teach her to go back to sleep after these wakenings. What you will do is go up to her room about 5 minutes before she typically wakes up. You are going to watch her, and as soon as she starts twitching/jolting, you are going to apply gentle pressure to her arms/legs. The first couple of times you do this she may still wake up all the way. That's OK. Each time she's going to get better at falling back to sleep. Even if she opens her eyes, continue with the gentle pressure (wihtout interacting with her) until she protests. Soon, she will fall back to sleep with that gentle pressure helping her. After about 3 days or so, you'll see her beginning to transition without your help! Then you stop helping her along and just let her do her nice sleep thing!
Don't worry -- you won't become a prop. I have no idea WHY we don't become a prop when we do this. They simply need our help to re-learn to go back to sleep, and then they are fine! 3 days is about how long it takes, but it might take less or more time. I've rarely seen it take more, so just plan on being available at every nap time. Set a timer so you don't miss the mark because consistency is key.
