Sounds positive to me too! i did a test with FMU on DPO 9 and it was the feintest of faint lines.... it got darker over the next few days. i don't think i have ever got a feint line if it wasn't positive. The doctor told me the chances of a false + were so much slimmer than a false - .

I would tell your sister to do another test tomorrow - OH hang on you posted on December 13th! is she pregnant?? Please let us know!