It was necessary to cultivate a good relationship with one’s in-laws. There were several well-known Muggle books on the topic. These expounded on the importance of harmonious family unity and of exposing children to both the mother and the father’s relations, and naturally for half-blood children this was ever-more crucial, as on Mum’s side the grandparents could not be drawn into conversation over safety measures in Quidditch, or the healthiness of Fizzing Whizbees, or even Why We Do Not Tolerate Martin Miggs In This House.
And she liked her children’s other grandparents, besides. At bottom, she did. They were not perfect (in essence, sometimes the whole family could be a nightmare, but then that was every family, and this one at least had funny, grinning cousins and kind aunts and uncles aplenty). But they did try to be good, and welcoming. Even to the most occasionally-snotty Muggleborn girl. And one simply had to take them on one’s own turf, as suggested in the sole magical resource on the topic, a Witch Weekly article by Filia Matricida entitled, No, Darling, I Haven’t Turned Your Mother Into A Toad.
So she invited them on an educational sojourn to the second-hand bookshop with the children. And for the first ten minutes it went smoothly, though Granddad demanded where the books on plugs were, and Grandmum said very loudly that she was quite sure the store cat with the impudent stare was part Jarvey.
But then they found it.
"Oh!" their daughter-in-law said hurriedly, horrible visions of Scarlet Women dancing in her head, "Well, of course the Muggles don’t know. They’re not really perverse or deviant or—”
"Just that they think we are?” said her mother-in-law, in that wretched tone that suggested she might begin to yell very soon.
"They come up with the silliest ideas," said her father-in-law, with that condescension that always made her want to smack his freckles off his face.
Hang them, she thought. “Well, misinformation between magical and Muggle cultures that cuts both ways! Muggles are hardly the only folk to assume things. Why — just the other day you asked why they didn’t all do the sensible thing and teach themselves to speak one language!”
"It’s not like they can learn those complex new translating spells," muttered Granddad.
"I don’t see what that has to do with anything," said Grandmum, "What really troubles me is how they want to give all the credit to the Dark Wizards!"
"I…what?" Hermione said.
"If they’re going to discuss the two-headed hippogriff—"
"The what—” Hermione said.
"—which ought to be in its own section, where the children aren’t likely to stumble on it, then they should stop, stop—”
"Fetterizing," said Arthur, "I think. That word you used last week, dear."
"Fetishizing…?" Hermione said slowly.
"What a horrible thing to say in public, honestly; both of you! In any case, the Muggles should stop assuming it’s Black or Dark! When really it’s such a lovely, private thing."
Hermione stared at her mother-in-law.
"We did have seven children,” Molly said primly.