From the Norman Rockwell Museum website:

At 73, Rockwell had lost the energy to develop his work in the painstaking way of the previous half-century. Now he would often omit the intermediary step of preparing a detailed charcoal drawing before proceeding to paint in oil. In addition, his color perception was diminishing due to cataracts. Still, his work continued to reach an appreciative audience.

In his illustration of suburban integration in Chicago's Park Forest community, Rockwell was secure in expressing his philosophy of tolerance. We can see the children will soon be playing with each other, but the face peering from behind a window curtain makes us wonder how the adults will fare.