We had the same Karma.
An absolute sweetheart until the DM would send prying WhatsApp messages. “Nice photos DD, but what about photos of MzHz and MiniMstrHz?”
She didn’t send any but wtaf?
That was day 1. Day 2 and 3 were great until we got back of an evening and more WhatsApp messages niggling at her. So she became rude, surly and just bloody awful.
The wifi ‘broke’ after that...
She only got to her once more just before the end of the break and it was so bad we had to actually pull her up and ask her directly what had been said to her to upset her and that we weren’t here to have everyone on eggshells because of this, so to stop it and be the lovely person we knew she was
Job done.
The next year we found a house in the middle of an island with no wifi and no mobile signal... obvs we did not tell her anything about this. Just that potentially there might not be Wi-Fi so to bring books and games just in case.
Sadly the ex scuppered everything anyway by convincing the child that 2 weeks was too long, that she’d be bored, that she’d miss her mum, that she’d be traumatised because her best friend was moving to another country absolutely nothing to do with where we were from/going.
SD had her brain absolutely fried by the DM and was so unbelievably cruel in laughing and saying she wasn’t going to come and tough etc...
So we never invited her again. Our holidays are boring? Right... no worries
Holidays without her and her bile dripping mother tagging along through the power of tech are bliss.