OK.....what I'm getting from this is she left home at 3:40pm, and *if* she's at the mall at 4:15pm, it seems she didn't have any intention of going to the birthday party. This is way past when she was supposedly going to meet her friend and walk the rest of the way to the party. :waitasec:
Not necessarily...she was leaving at 3:40 to meet a friend on the way at 4:00, so would assume the party would start after that as they wouldn't meet at the same time the party was starting, could have went into mall to kill time or pick up a gift, the mall is in between her house and where the party was supposed to be so even if the party started at 4:30 or 5:00 that is plenty of time to make it there as it would be only about a 5 minute walk from the mall.