The Real Housewives Of Beverly Hills star took Cibrian and LeAnn to task on Wednesday night, responding to an open email from her ex with her own abusive and hate-filled rant.
In it Brandi accused LeAnn of being a heavy drinker, addicted to prescription drugs, having 'severe mental issues' and putting her children in danger.
She labelled the singer angelfish 'because she sings like an angel and drinks like a fish' and told her ex to 'man the f*** up, put the tequila down and be a proper parent.'
Brandi's claims were strongly denied by a representative for the singer, who told MailOnline the reality star was' 'spewing forth inaccuracies, rants and half-truths,' and added: 'None of Brandi’s allegations are true. People need to see it for what it is – publicity'.
Brandi later removed the tweeted message and admitted it had been a mistake, saying: 'I'm taking email down I was in defense mode after seeing [Cibrian] put his online.
'Let's not talk of them anymore I was wrong 2 put it up.'
Brandi's rant was just the latest in a series of exchanges between the two families.
It began when an interview was published on Us Weekly on Wednesday morning in which Brandi accused LeAnn of having a 'severe eating disorder' and claimed her son fell ill after swallowing one of the country star's laxatives.
The 40-year-old branded LeAnn 'unstable', adding that she didn't want Mason, nine and Jake, five, to be around her alone.
In the interview Brandi said: 'LeAnn has a severe eating disorder. She has [a laxative] in every purse.
'Mason, my eldest, ate some of Le's candies and got extremely ill. And Le's candies are laxatives,' 'It was a big f***ing deal for me, and I lost my mind.'
'Mason found on on the floor and thought it was a Skittle! They don't keep sugar in the house,' Glanville explains. 'He thought he finally found candy.'
She added: 'I, unfortunately, don't find her to be stable and I don't want her around my kids when Eddie's not there - or at least the nanny, his parents, someone.'
Defensive: LeAnn Rimes with Eddie Cibrian before the online clash with Brandi GlanvilleCibrian then responded to Brandi's interview with a public email of his own which was published on Radaronline.
The 39-year-old weighed in saying: 'It is absolutely ridiculous that my ex-wife continues to put the personal lives of myself, LeAnn, our sons and my family on public display for the sake of her notoriety.
'She is fully capable and has the means of contacting myself and LeAnn privately to discuss any matter concerning the children.
'The fact she chooses not to, should be pretty transparent. And while I do not wish to fuel her ever-igniting fire, there is a breaking point where enough is enough.'
And he added: 'One day when wine and narcissism are not consuming you, you will realize how fortunate the kids are to have LeAnn in their life. She is amazing with them, as the kids will 100 percent attest to.'
He continued: 'The love they have for their "bonus mom" continues to grow each day as we navigate the changes to our family; a fact that Brandi cannot argue as she herself has stated as much.
'If my ex-wife truly cared about the welfare of our sons, she would stop the constant bashing on an important person in their lives and focus on productive co-parenting to make our blended family the strongest it can be. And she would do so privately. Let's see...'
In response Brandi published her email on Twitter.
LeAnn, who underwent a 30-day treatment program for stress and anxiety in August, has previously denied suffering from an eating disorder.
The confrontation comes less than a week after Brandi hit out at the country singer, 30, for referring to her stepsons as 'my boys' in a Twitter post.
'They are my boys, Eddie's boys and your stepsons... for now,' a furious Brandi tweeted on November 30.
She has also recently criticised LeAnn after she posted a video of one of her stepsons riding a bicycle without a helmet.
Eddie dumped Brandi, his wife of nine years, in 2009 after beginning an affair with married LeAnn on the set of their film Northern Lights.
He married the Blue singer in 2011.