35, male, I have this dent in my forehead & I’d like to know what caused it? (Photo)

I’m a 35 year old male and I’m 6 foot tall. I have this vertical indentation in my forehead. I am curious what has caused it and how I could get rid of it. It could be genetic because my 15 year old son also has it. It’s just less prominent on him. I have seen thing such as side sleeping, but is it just due to my bone structure in my brow ridge? I’d love to hear tips and tricks and any recommendations.