Bombshell court papers filed this week by Southern Charm star Thomas Ravenel as part of his ongoing custody battle with Kathryn Dennis accused the mother-of-two of using drugs and drinking alcohol during both of her pregnancies.

According to the documents, Ravenel, 56, argues that his four-year-old daughter, Kensington Calhoun, and his three-year-old son, Saint Julien Rembert, have 'developmental and behavioral' problems caused by their mother's conduct during and after each pregnancy.

Dennis' attorney has denied Ravenel's allegations.

Ravenel says his daughter has been undergoing intensive therapy to address her issues, which he attributes to 'lack of bonding' with her mother in her infancy.

Documents filed by Thomas Ravenel (left) accuse Kathryn Dennis of taking drugs and drinking alcohol during both of her pregnancies, resulting in developmental problems for their son and daughter (pictured with their mom, right)

According to the father, his son also has been in therapy because of Dennis' alleged drug and alcohol abuse 'in utero,' the court papers filed in South Carolina state.

The filings were first obtained by The Blast and later reported on by People.

Dennis' attorney has dismissed Ravenel's assertions outlined in the complaint as 'defamatory allegations.'

Ravenel's lawyer parried by pointing out that allegations 'do not constitute defamation if they are, in fact, true.'

In 2016, Dennis lost custody of her children after failing drug tests and Ravenel became the sole caretaker of his daughter and son.

After a stint in a rehabilitation facility, Dennis was awarded a shared custody with Ravenel, which he decried in the court documents as being detrimental to tear children’ progress.

Since then, Dennis has being waging a legal battle to win primary custody of Kensington and Saint.

Ravenel claims Dennis, 26, has been buying synthetic urine so that she could pass drug tests while continuing to abuse pills and alcohol

Ravenel's court papers claim daughter Kensington and son Saint have required intensive therapy as a result of their mother's actions during and after each pregnancy

To that end, the reality TV star used sexual assault allegations from two separate women against Ravenel to help bolster her case against him.

In turn, Ravenel accused Dennis of being motivated by her desire to resume her role on Southern Charm by constructing a narrative of a 'rehabilitated Mother who regains possession of her minor children,' according to the court papers.

According to Ravenel, Dennis has been pursuing the custody battle with the blessing of the Bravo show’s producers hungering for dramatic fodder for the next season.

The court documents state that Ravenel believes Dennis bought, sold and traded prescription drugs with 'friends, cast members and show producers'.

Ravenel further claims that as a result of spending more time with their mother, both his son and daughter have developmentally regressed.

The father cites as a specific example Dennis' alleged failure to potty-train their son and continuing to bottle-feed him.

The 56-year-old's allegation against Dennis, 26, was made in court papers related to the former couple's ongoing custody battle over their two children. They are pictured here in 2015

In another shocking revelation, Ravenel’s latest court filings allege that the mother of his children has been procuring 'synthetic urine' that has allowed her to pass drug tests while continuing to take prescription pills and drinking alcohol.

According to the documents, the mom-of-two becomes 'overwhelmed' after spending more than a few days with her children and turns to controlled substances to cope with stress and anxiety.

Ravenel also says Dennis has been diagnosed with multiple mental health conditions, including bi-polar disorder, obsessive compulsive disorder, attention deficit disorder, self-mutilation and kleptomania.

Ravenel claimed Dennis had been intoxicated by prescription and/or illegal drugs while caring for their two children. Dennis is pictured with the children during the holidays

Dennis filed court documents in December that raised claims Ravenel had paid one of the women who accused him of sexual misconduct $200,000 for her silence.

Dennis argued in the filing that since their custody agreement was put in place in 2017, 'many new things have come to light'.

Ravenel was arrested in September after former nanny Dawn Ledwell claimed she was in his Charleston, South Carolina home in January 2015 when he allegedly took off her pants and fondled her.

He now awaits trial over those charges. Ledwell also filed a lawsuit against him.

Ravenel was subsequently dropped from the show, as well as Bravo and it's parent companies.

Ravenel is already a felon. He was arrested in 2007 less than a year into his term as South Carolina treasurer after he bought cocaine for himself and his friends. The real estate developer pleaded guilty and spent 10 months in prison.

In 2014, Ravenel pleaded guilty to driving under the influence on Long Island, New York, resulting in his license being suspended for six months.