The news comes after Thomas Jr. sent the Queen a bizarre letter saying, among other things, that he think the royal family has turned Meghan into a "zombie" after she married Prince Harry, as RadarOnline.com exclusively reported.
On Friday, July 20, the woman who could become Meghan's sister-in-law, Darlene Blount, was busted in Grants Pass, Oregon, at the couple's home.
According to reports, she spent a night behind bars at Josephine County jail and was bailed out on Saturday, July 21.
Blount, 37, was charged with assault in the fourth degree, the Daily Mail reported.
A source told the Mail that "there was a domestic violence call at the home of Thomas Markle Jr and Darlene Blount. Darlene was arrested on assault charges."
It isn't the first time the two have allegedly been involved in an altercation.
Blount wound up in a mugshot earlier this year after being arrested on New Year's Eve in Oregon for assault, suspected of hitting her fiancé, 51, in a boozy fight.
In the 911 call from back then, Blount claimed to the operator that Thomas Jr. had been threatening her all night, claiming he was being "really f***ing weird" and was beating himself up.
Once police arrived, however, they didn't buy Blount's story and arrested her after they found Thomas Jr. gushing with blood.
Previously, Thomas Jr. was arrested on Jan. 12, 2017 in Oregon for allegedly holding a gun to Blount's head during a drunken argument.
He later apologized, but in a bombshell interview with RadarOnline.com, Thomas Jr. made excuses for the domestic attack on his girlfriend.
He claimed about the gun, "It was unloaded. There were no bullets in it. Everyone makes mistakes. This time I made a bad one but we all do."
More recently, Radar has reported on Thomas Jr.'s wild letter to Queen Elizabeth, in which he begs her to give his father Thomas Sr. a royal title, and expresses the worry she could die like Prince Harry's mother, Princess Diana.
He also believes Meghan has been looking like a zombie and "prisoner" of the royal family in the handwritten note exclusively obtained by Radar.
Their father, Thomas Sr., has caused shock with controversial interviews he has done about Meghan and the royals after her May 19 wedding to Harry.
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