Ok, so I do know that Mothering Sunday was originally the day when a religious Xian was supposed to go back to their "mother" church; and I read that an American started a memorial service for her mum in 1907, but that has no connection with the UK version. It probably developed from the old religious tradition, and as fewer people did the church thing, maybe it morphed into the celebration we have today.
Before my mother died, it would be a day when I treated her to the lunch of her choice (which varied between a local Chinese dive, Côte or the Wolseley). Now it is a day to think fondly about her (I'd eat Chinese in her honour, but haven't yet found a decent local place here).
These photos are of Evelyn doing something she loved to do. In them she is near Potsdam with her friend Eckerhard, z"l, visiting Eric Mendelsohn's Einstein Turm. Travel, architecture, a dear friend - a lovely day for her, and a lovely memory for me.