"Stop grizzling!"
Grizzling being crying that the onlooker considered unjustified. eg - you "cry" if you have a broken leg, but you "grizzle" if you are shedding tears and making distressed noises because your Mum won't let you have some sweets in a supermarket.
My Mum used to say "Mon Dieu!" but in her Sarf London accent it sounded to me like "Mange" and I couldn't understand why she said the French word for "eat" when exasperated. (She also called me a daft ha'p'orth and I too thought an Apeth was a kind of Yeti)
My stepfather used to say, when describing someone large and burly, that they were "built like a shithouse door." I know the phrase is supposed to be "built like a brick shithouse" but I rather prefer his version of it.
My Dad used to call us "cloth ears" - I don't know whether that was when we weren't listening or just being dim.
When we left the door open it was "were you born in a bus?" not born in a barn as most people say.
"Willy" was considered far too vulgar a term for us to use. Penis? What was THAT? No, in our house, the main male reproductive organ was . . . wait for it . . . a tassel. Cue much spluttering when we heard about "Joan's new curtains, gorgeous they are, with lots of lovely big tassels on them."
Female genitalia was one's "fluffy bit." 