Bride-to-be Heidi Withers was chided by her future mother-in-law for her "lack of grace" according to a cutting email that she shared with friends.

The email purportedly from Carolyn Bourne warned her stepson's fiancée about her poor etiquette.

But after Miss Withers, a PA, forwarded the email to friends, it quickly spread and became the talk of the Internet because of its high moral tone.

In the email, Mrs Bourne, from Dawlish, Devon, apparently tells off Miss Withers, 29, for the way she behaved when visiting the family in Devon in April.

It describes the behaviour of Miss Withers as “staggering in its uncouthness and lack of grace.”

Mrs Bourne, whose apparent moral attitude is reminiscent of the Countess of Grantham's in ITV’s Downton Abbey, reportedly warns her prospective daughter-in-law: “If you want to be accepted by the wider Bourne family, I suggest you take some guidance from experts with utmost haste.”

The email goes on: “Here are a few examples of your lack of manners: When you are a guest in another's house, you do not declare what you will and will not eat – unless you are positively allergic to something.

“You do not remark that you do not have enough food. You do not start before everyone else.

“You do not take additional helpings without being invited to by your host.

“When a guest in another's house, you do not lie in bed until late morning in households that rise early. You fall in line with house norms.

“You should never ever insult the family you are about to join at any time and most definitely not in public.

“You regularly draw attention to yourself. Perhaps you should ask yourself why. No one gets married in a castle unless they own it. It is brash, celebrity style behaviour.

“If your parents are unable to contribute very much towards the cost of your wedding, it would be most ladylike and gracious to lower your sights and have a modest wedding as befits both your incomes.

“One could be accused of thinking that Heidi Withers must be patting herself on the back for having caught a most eligible young man. I pity Freddie.”

The man in the middle – prospective bridegroom and businessman Freddie Bourne, 29, from Putney – was trying hard not to inflame the situation.

“I’m not commenting on the matter,” he said.

(Read by Nelly Min. Nelly Min is a journalist at the China Daily Website.)