There Won't Be Trumpets - S1-E17
Trivia: Bree and Lynette are walking to Juanita's funeral. In the original broadcast Bree said, "You have to hand it to Gabi and Carlos. They do grief better than anyone." However, her mouth doesn't say "Gabi and Carlos," but rather "the Catholics", and the audio has a noticeable change at that point. Also, the closed captioning just says "them". It seems that the line was changed in post-production with an overdub, possibly due to the Pope dying around the same time. The correct version is on the DVD.
Chosen answer: Poker. They have been playing that this whole time, once a week with everyone who was invited that lived on the Lane.