Whitney Houston & Bobbi Kristina: The Cover-Ups!

The killings were linked by drugs and presence of Nick Gordon, investigators claim.

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The bathtub murders of superstar Whitney Houston and her young daughter Bobbi Kristina Brown are related — and cops need to reopen the investigation into Whitney’s watery death!

 That’s the call for justice from one of America’s former top law enforcement officials following the Jan. 31 one-year anniversary of 22-year-old Bobbi Kristina’s drowning. John A. Carman, a former Secret Service agent, told The National ENQUIRER, “This smacks of a double cover-up!”

Meanwhile, this publication has also learned another investigator, Isaac Weishaupt, has determined there is enough “evidence” to show the deaths could be related in both circumstance — and motive.

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Both deaths are linked by a combination of drugs and Bobbi Kristina’s abusive boyfriend, Nick Gordon, 25, who was either near or at both death scenes.

“Whitney Houston ends up dead in a bathtub, covered with bruises, under hinky circumstances,” declared John. “Three years later, (Bobbi Kristina) dies in a bathtub, also covered with bruises, under hinky circumstances.”

Authorities have yet to release Bobbi Kristina’s autopsy results since her July 26 death, pending the outcome of a Georgia grand jury investigation.

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The authorities are also keeping quiet about the possible indictment of Gordon, who is already accused in a $40 million wrongful-death lawsuit filed by Bobbi Kristina’s estate for allegedly beating her and giving her a “toxic cocktail” that knocked her unconscious.

While Gordon vehemently denies any wrongdoing in Bobbi Kristina’s death, “the case remains open and under investigation,” Yvette Jones, a spokesperson for the Fulton County District Attorney’s office, told The ENQUIRER.

An autopsy that followed 48-year-old Whitney’s Feb. 11, 2012, death at a Beverly Hills hotel determined it was an accidental drowning with cocaine as a contributing factor.

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John, who has worked hundreds of drug cases, said to solve the case, detectives must reopen a Whitney probe.

“Whitney’s case was dropped by Beverly Hills cops who didn’t do a proper forensic investigation,” he charged.

“Her autopsy report had more questions than answers, and is frankly laughable as a legal document.”

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In a bombshell 2012 report, Bobbi Kristina’s aunt, Leolah Brown, the sister of Bobby Brown, Whitney’s ex-husband, charged it was no accident and expressed fears for the young woman’s safety!

“Once all the dots are connected, whoever’s in the hot seat will be lucky to ever see daylight again,” she said.

Meanwhile, the haunted three-bedroom Roswell, Ga., townhouse where Bobbi Kristina spent her last waking moments is now up for sale, listed on Zillow for $469,000.

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While the online listing does not mention the death, the bathtub where the aspiring young singer was found facedown and unconscious is prominently displayed!