Fifi Geldof has lashed out on Twitter at critics of her sister Peaches, in an expletive filled tirade.
A Twitter backlash began after an inquest found Peaches died of a heroin overdose in the family home in Wrotham, Kent, with her 11-month-old baby son Phaedra with her body for up to 15 hours.
Police discovered a syringe containing residue of heroin inside a sweet box next to the bed, and other drug paraphernalia including burnt spoons, syringes and knotted tights throughout the property.
As details of Peaches' death emerged, many social media users branded her irresponsible for taking drugs near her child.
An Instagram site user accused the late TV presenter of having been "selfish to use drugs in front of them (the children)."
Peaches was also attacked on Mumsnet yesterday, where one website user called her a 'toxic hypocrite' for potentially exposing her child to drugs.
Controversial wannabe model Josie Cunningham, who became notorious after revealing she considered aborting her baby in order to appear on a reality show, also came under fire online yesterday after she claimed Peaches' drug addiction was 'pathetic' and 'a choice.'
On a thread which was later taken down, another person wrote: "Seems like the reality was the exact opposite of how she portrayed herself."
Former Apprentice contestant Katie Hopkins also controversially refused to sympathise with Peaches Geldof following news of her death.
Fifi responded to what she called the "viciousness" of the reaction to the mother of two's death in April, defending her younger sister Fifi responded to the claims saying: "You've no idea what you're talking about. Don't keep calm and f*** this. F*** that. F*** you. F*** off."
"Sums it up nicely about how I'm feeling about the viciousness today. Maybe now she'll be allowed to RIP," she added.
When another website user claimed her sister was 'selfish and sad' for using drugs, Fifi replied: "You've no idea what you're talking about quite frankly. Yet another who has bought into the bulls****".
She later thanked her followers who had posted messages of support.
"Thanks for your beautiful words of love and support for myself and Peaches. I appreciate it more than ever today," she said.
The daughter of Bob Geldof and Paula Yates, Peaches died of a heroin overdose, reportedly ten times bigger than the one that killed her mother Paula Yates 14 years ago.