Small act of kindness by a stranger

I don't know her name. I don't know her story. But I do know her smile. My daughter and I carpool to work and every work week day we pass a small, well-kept home on the corner. A woman is often standing in her yard with her dog on a leash, walking around clearly enjoying her time with her pet. She gives us a big smile and an enthusiastic wave. She makes our day. People don't wave to each other as much anymore. So we found ourselves surprised the first time this woman waved as if we were her long lost friends. 

I sometimes want to stop and let her know how we now look forward to her smile and wave. We find ourselves disappointed if she's not outside when we pass. Her simple, kind act reminds me how much a simple smile and hello means to us.