As a dutiful son I still visit my elderly parents every Sunday afternoon for "dinner". It's a good way to keep up to date with them without looking like I'm checking up. Besides, my Mom is still a better cook than I am. Traditionally we had our biggest meal of the day, (supper), in the evening every day except Sunday, when it was served at 3:00 and called "dinner". A beef or pork roast ,or chicken, was/is common Sunday fare. There were certain items, like Italian food, that were for some reason never served on Sunday. Also, since my Father has never been a big fan of desserts, Sunday is the only day my Mother will bake a pie or something.