Downton Abbey cast members have now been banned from bringing their pets to the set.

The estate's owners, the Earl and Countess of Carnarvon, made the pet ban because they say the number of pets running free in the grounds have became unmanageable.

The Lady Carnarvon's own dogs were being upset by the number of pets on the Downton Abbey set....so she made the ban.

"One of her own Labradors gets jealous when rival dogs are on set," a source said.

The Lady Carnarvon, 49, has two Labradors and three spaniels at her  £150million country mansion in Hampshire.

A show source said: "As the cast spend so much time filming at Highclere Castle, a lot of them bring their dogs with them. Lady Carnarvon imposed a ban because she doesn't like the dogs going in certain areas in case they cause a mess.

Ed Speelers, who plays Jimmy Kent, the downstairs footman, talked about the mess his pooch made, saying,

"I've got a border collie who ran off and up to the part of the house you're not allowed to go to. I had to run after him and pick him up by the scruff of the neck because he was getting mud everywhere."

Uh-oh.

Still, some of the Downton Abbey actors are not happy...and some of them are even breaking the rules.

Dame Kiri Te Kanawa, 69, who plays the Australian diva soprano Dame Nellie Melba fessed up to being a rulebreaker "I took my two dogs along and Lady Carnarvon didn't want those anywhere near the place, but anyway I did."

The fourth season will open with the Crawley family still reeling with the death of Matthew Crawley, the heir to the estate. Meanwhile, downstairs, the kitchen will be reeling with the march of modernity via new kitchen equipment.

Lord Anthony Gillingham, played by Tom Cullen, will join the Downton Abbey cast and is expected to be a possible love interest for the recently widowed Lady Mary.