Reflections, Light, How does it work? - A Science Question for Anyone Who Can Answer

At a recent party my God-father, sister, and I were amazed at the questions that his grandson was asking about the world around him. Such as "Why can I see through the window, but not put my hand through it?" Big question for an 11 year old.

My sister then came up with:

When sitting on a train, bus, etc. I can look in the window that I am
sitting directly beside (on an angle) and I can see not (only) the reflection of
what is across the train from me, but I can see a reflection of what/who is
sitting in front of me even if they are several seats ahead. How does this
happen or how can it be explained? A simple version of this is if I hold a
small mirror right beside my right eye and something in my left hand, I can
extend my left almost to arms length and still see the reflection of the item in
the mirror. How does it reflect back when it is so far forward of the mirror?

I've emailed this to Bob McDonald, host of CBC's Quirks & Quarks. I'm hoping I get an answer from him or any one else that cares to answer. Things that keep me up at night.....lol.