Meghan, the Duchess of Sussex, meets guests as she attends the 'Your Commonwealth' Youth Challenge reception where she and Prince Harry met with youngsters from across the Commonwealth, at Marlborough House in London, Thursday July 5, 2018. Picture: AP

The Duchess of Sussex is facing fresh embarrassment at the hands of her American family.

Meghan’s future sister-in-law Darlene Blount was arrested at the weekend in the latest of a string of violent incidents.

And on Sunday night police mugshots of Miss Blount – bride to be of the duchess’s half-brother Thomas Markle Jr – were again making news around the world.

Miss Blount, 37, was arrested in Grants Pass, Oregon, on Friday on a charge of assault, it was reported.

Few details are known about the incident, but a source told MailOnline: "There was a domestic violence call at the home of Thomas Markle [Jr] and Darlene Blount. Darlene was arrested on assault charges."

She was released on bail on Saturday, a deputy at Josephine County Jail said.

It is the latest unfortunate incident involving Meghan’s half-brother. Police were called to the home of Markle and his fiancee on New Year’s Eve.

On that occasion, Miss Blount told the 911 operator her 51-year-old boyfriend was being "really ****ing weird" and was beating himself up.

Miss Blount said Markle had been drinking when he became jealous, thinking she was trying to have sex with a man she knew when out at a local bar.

She claimed to be scared of Markle because he is "a big guy" and suggested to the operator that he could be mentally ill.

But when police arrived at the couple’s home, they did not believe Miss Blount’s story and arrested her for assault.

She spent two nights in custody at Josephine County Jail but the District Attorney decided not to press charges and released her.

The couple later described the incident as a wake-up call and said they were seeking relationship and alcohol counselling. In 2016, Markle was arrested for allegedly holding a gun to Miss Blount’s head during another drunken row.

Prior to his relationship with Miss Blount, Markle was married for 11 years to Tracy Dooley, a florist who was reportedly a recovering alcoholic.

They divorced in 2001 and have two sons, Tyler and Thomas. Tyler works as a cannabis farmer in Oregon – a state where marijuana is legal – and has said he plans to create a heady hybrid called Markle’s Sparkle.

Thomas is the manager of a fast food chain restaurant.

Although not invited to the wedding of Meghan and Prince Harry, the pair were among members of the Markle family to fly to London for the event.

While in the capital, they created headlines after Tyler had a knife seized from him by a nightclub bouncer. When police arrived at the hotel where he and his family were staying, they found Thomas had an illegal pepper spray.

Officers confiscated the weapons and issued warnings to both brothers, who are said to have admitted bringing the items through customs. 

At the time a source close to the family told the Daily Mail: "Tyler is upset at the thought of no longer ever having the chance to see his Aunt Meghan again and bitter at not being invited. It appears he has been carrying the knife down in his back pocket the whole time he has been here.

"He told people at the club he usually carries a gun at home and was asking if London was really dangerous. He said earlier in the week he had been concerned about terror attacks.

"He apologised to the police without making any fuss so he could fly straight back without a criminal record. The rest of the family are distraught."