I just noticed part of Mylos left eye is red. Sure this might seem like a bit of an overreacting post but I've never seen Mylos eye like this.
Could it be from playing with Prince? Or some infection?
He's acting normal though, he's isn't squinting and he isn't pawing his eye or anything. Should I be concerned or just keep watching him?

Dave, It looks like he may have been poked, probably while playing with Prince. Just watch it, and how he is acting. If it becomes all red, then a trip to the vet to see if it's infected, you mentioned the symptoms to look for, so if he starts pawing, shaking his head, or activity and food intake lowers it's a vet visit.

As Renee said, probably a poke. Or if he rides with his head out the window potentially he was hit by a bug. I watched Kenzi get nailed square between the eyes once by a june bug. Funny as all get out but it about knocked her unconscious. You can use normal eye wash or saline solution to clean the eye in case there's a little bit of dust or dirt in there that could be causing the irritation if you wish. If it doesn't clear up or you see other symptoms definitely see a vet.

Thanks @MiyasMomma and @Twisterll
I just wanted to ask here to see if what I was thinking correctly about this.
I've never seen his eye like that. So Im gonna go with he got poked while wrestling with prince haha cause he hasn't had his head out the window today.
These two puppies get crazy and only getting more nuts as Prince slowly gets bigger