Before I continue using her lingo, 'I thought', it'll be a good idea to look up what Gram's phrases actually mean because I've been known to throw out some words that have totally different meanings than what I originally thought, such as "tube steak", thinking it actually meant hot dog.
Both "cat's pajamas" and "bees knees" originated in the 20's and was part of the typical vocabulary of the flappers, young women whose avant garde wardrobe and free-spirited disregard of social conservatism epitomized the spirit of the Roaring Twenties. My grandmother certainly was all of that and more. I miss her.
"Cat's pajamas", and "bees knees" both mean "that is great", "wonderful", or "the hottest new thing". I kind of figured that out based on how it's used in context. But you never know. At least I haven't embarrased myself too much this time.
Anyone under 50 always laughs and questions the phrase, "Hey that's the bees knees." Now I know where it originated and can explain the history along with the wonderful memories and spirited presence my grandmother continues to give me.