My Son Is 4 And Scraped His Forehead-the Wound Was

My son is 4 and scraped his forehead-the wound was very shallow-it was truly a small scrape. We put neosporin on it daily and kept it clean. Within a few days it developed a light scab and then the scab fell off. However, the skin still has not healed, 6 weeks later. It's not a scar as it doesn't have that consistency. It still just looks like a very shallow, pink open wound. It's not infected, but it won't heal. I'm starting to get concerned that it's some kind of weird mark that isn't going to go away! I'm keeping up with sunblock and mederma but the cut looks exactly the same as it did five weeks ago. Thoughts?