It's most likely that all is well and that the guidance you received last year is still applicable. However, a year has passed and you are doing the prudent thing by calling this to the doctor's attention. The most frequent reason for such occurrences in young children is a state of constipation or impacted bowels and sometimes it's not evident that this is happening. Be sure to have it checked out - it may be what is causing the difficulty.
with an anterior anus, your daughter may have some problems with soiling, she may not be totally emptying....i suggest seeing a pediatric surgeon who could probably do some testing to determine if the displacement is causing her this problem good luck