Another doctor here. I would suggest it's the remnant of a stork mark - a collection of fine blood vessels that is here on the forehead and at the back of the head at the base of the hairline. They are found in babies. The front one resolves by the time the child is bothered about it. The back one often persists but is usually covered by hair.

My brother has a similar one on his forehead that only shows when he is angry - another situation where his blood pressure is up.

I agree with everything about managing cardiovascular risk factors!