We had the same experience. One twin was accepted, the other waitlisted (basically a rejection). The waitlisted twin was ambivalent about going and it showed during her interview. She applied the next year for 10th grade, was much more positive and focused during the interview, and was accepted.
Note that we could have made a big deal about it and really pushed for second admit but decided not to. It was better for her to go to LPS and then be much more motivated to reapply.