From what I understand, the love bugs are usually gone by October 1st. Their fall "season" usually occurs somewhere during the last 2 weeks in September and only lasts 7 to 10 days.
So while you'll hear some horror stories from people like yourself who unfortunately arrive at the height of the love bug season in the spring (in May) or the fall (last 2 weeks in September), I believe you'll be very lucky! For all practical purposes, their season will be ending or already over by the time you arrive. I suspect the WORST you can expect is the very tail end of their season for the first couple of days you are there.
In other words, I think they'll already be pretty much GONE and your family will have a FANTASTIC vacation. Your daughter's ears should survive the trip completely unmolested!
Best wishes,
Dave