Recurrence Preauricular Sinus/Pit after 5 Excisions

I last posted here in 2008.  My son is 8.5 and has had 5 surgeries on his preauricular sinus/pit, the last of which was radical and scraped cartilage away from his scalp.  About one year ago my husband and I noticed our son had what appeared to be a large pore develop in his external ear canal, fast forward to now and we are thinking it is a recurrence of the sinus/pit as I took him to our GP and although GP said an enlarged pore when I asked about the pathology of his last operation the GP was surprised to see that several tracts of the sinus were left behind.....could this be a recurrence of the sinus/pit in his external ear canal, it has enlarged somewhat and is a darkish red/purple colour yet translucent, so when I use a cotton bud softly around the area there appears to be movement of a pus coloured discharge under the surface of the "enlarged pore".....what do you all think, have you heard of a recurrence within the ear canal itself? Many thanks to all, worried mum in Australia.