There have been lots of negative stories about Kate and bullying allegations against Kate. Stories from other students about her stalking William and chasing off any other women who tried to get near, making sure she was the only woman around him. Stories about her mean girling his female friends. The fact she had few or no friends at her wedding, just Will's friends. There was a private forum for St Andrew's students which a journalist managed to get access to during the engagement and he found old posts dating back to 2001/2002 complaining and making allegations against Kate, including claiming Kate copied other students' work in exams. Maybe just jealousy but she was evidently not well-liked by other women during her time at university.
Her boss when she worked briefly on a yacht sold an interview to the Daily Mail implying she used it to meet rich men and would wear inappropriate clothes and basically flash. Her old school head did an interview saying she got in trouble because she was addicted to mooning people.
After they moved to Amner a number of staff quit and the Daily Mail ran a big article claiming the "Cambridge staff exodus" was because Kate was lazy, demanding and refused to pay attention to royal protocol, and that she let Carole run the household and that Carole was domineering and ordered the staff around.
The Sun ran a headline claiming Amner staff had nicknamed her "Princess Prickly."
Carole and Pippa both were criticised for profiting from their royal connections and giving so many interviews, including reports royal courtiers were concerned, and the Daily Mail ran an expose on Party Pieces and the many complaints from employees about Carole being abusive and staff feeling "terrorised" by her. Some of the details were things like salaried staff getting texts that they'd be fined for leaving work early for a doctor appointment, Carole summoning staff by clicking her fingers at them, and refusing to allow Christmas decorations or anything fun in the office.
An anonymous source leaked a story to the tabloids claiming Pippa was dating a titled man and his mum shut it down hard and said it was all lies and was obviously implying Carole had leaked it. The guy was never seen with or linked to Pippa again.
By all accounts Carole raised both her girls to do nothing with their lives except chase wealthy husbands, while her son was ignored.
A couple of years ago Kate fired her personal assistant manager Sophie Agnew while she was on her honeymoon, who did one of those "sources close to Sophie say" interviews to the Daily Mail about how mean Kate was to fire someone who'd been so dedicated to her and worked so hard while she was on honeymoon. A few months later Kate's private secretary Catherine Quinn quit without another job lined up after just two years of working for Kate. Just this year Will and Kate's chief secretary quit after 18 months in the role. Rebecca Deacon also quit. There was some other scandal about one of Kate's chief staffers leaving to have a baby and being told while she was on maternity leave that they'd changed their minds about her being allowed to go part-time. I think they had to give her a big settlement.
Kate goes through personal staff like water.