As I finished my post on this subject, I remembered something I’d read about John Wesley’s mother. I found this, supposedly, from Dick Eastman’s book, but I had to clean up the text. It gets the idea out there, however.
“Susannah Wesley, the mother of nineteen children, including John and Charles, had no specific place for prayer. So at the chosen time for her spiritual exercise she would take her apron and pull it over her face. Her children were instructed never to disturb Mother when she was praying in her apron.” (The Hour that Changes the World, page 21)