Observant much?

So I have lived here for just shy of 8 months now. I'm pretty nosey about anything I can see from my office window (or the kitchen window, or the living room window, or out the front door...). I look out every time a car drives by or a dog barks or I hear something outside. How is it that I never noticed that our neighbours have a teenage son? I see the adults come home from work every day! Apparently he is the elusive 15 year old boy. Either that or my nosey neighbour private eye skills are slipping. Yikes!