Bee sting

I recently donned my "summer" dressing gown and noticed something scratching my shoulder. Closer inspection revealed this object trapped in the fibres:

As far as I can determine it is a bee sting, which has presumably been in the gown since it was washed and aired in the autumn last year. Perhaps a bee "attacked" the gown while it was on the line, but it is rare for a bee to sting.