Neighbors

These two nests being so close made me wonder about how so many neighborhoods have changed.
I grew up in a neighborhood with houses nicer than ours and with houses that I took dinner to every evening because my Grandmother knew there was need. Today so many neighborhoods are "developments" where everyone has to make a similar amount in order to afford the house. "Need" is isolated rather than part of communities. (I hope that made sense)
I used to play in all the yards and on the street. The children in our area are now driven to activities.
I think I knew most of the families on my street growing up. Now, I know the people next door on both sides but they aren't people I would call friend or ask for help.
Where did that feeling of "neighbor" go? Why did it change?