Star watched Sue and Dana as she started putting her thoughts together. So Sue is Jared's sister and Jared does seem to be Dana now. She thought back to a little earlier, from what she had heard it seems that Anna knows about the medallion so she might be the real Dana. As to were Dan fits in she did not know.
When Star heard the announcement that Dana was pregnant she smiled a bit as she know that the medallion was not supposed to be able to change a pregnant woman. This could mean that Jared was now stuck as Dana.
She snapped her fingers "that might be what Anna was talking about when she came back from Dana's room."
She wanted to check if what she suspected was true so she texted Anna "I seen you at Dana's party, Did you know that Dana was pregnant."
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Upon getting the text from Star, Anna shocked she had suspected that the medallion did not work because Jared was about to start her period. Anna texted back "How do you know that."
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Star got the return text and the way it was worded, plus the speed at which it came back she know that this seemed to upset Anna to here the news.