Season 9: Episode 202: A Job for Robert
Ray becomes jealous when Marie starts treating Robert better than him. Ray finds out that Marie gave Robert a "gift basket" full of lotions, massage oil, candles, etc. Ray deduces Marie is just manipulating Robert by giving him all this, so it will put him and Amy 'into the mood'. She does this with the intention of eventually having new grandchildren. Robert sees this as wrong, and actually puts him out of the mood with Amy, not able to get Marie out of his head.