My baby's gone: Bobby Brown breaks down describing months he spent watching Bobbi Kristina lifeless in a coma as he speaks for first time about losing his daughter just three years after death of Whitney Houston

Bobby Brown is breaking his silence as he speaks for the first time about the tragic deaths of his ex-wife Whitney Houston and the couple's daughter Bobbi Kristina in a new interview.

The singer is also breaks down in tears during that interview as he describes to Robin Roberts just how agonizing it was to spend six months watching his daughter lay helpless and lifeless in a coma after she was discovered face down in her bathtub in January of last year.

Bobbi Kristina was immediately placed on life support and stayed in a medically induced coma until she died at the age of 22 in July.

'The hardest thing I had to do in my life was to tell my daughter to let go,' Brown tells Roberts in the interview while fighting back tears.

He then becomes unable to control himself, saying as tears stream down his face: 'My baby's gone.'

Scroll down for video

Difficult talk: Bobby Brown is opening up about the deaths of daughter Bobbi Kristina and ex-wife Whitney Houston for the first time in a new interview that will air Tuesday on ABC (above)

Too much: Brown breaks down in tears while describing the months he spent watching his daughter lay lifeless in a coma (Whitney and Bobby with Bobbi Kristina in 1999)

Love: Brown also talks about how similar the deaths of his ex-wife and daughter were, with both women being found in a bathtub and drugs playing a role (Whitney and Bobbi Kristina above in February 2011)

Brown also tells Roberts during the interview, which will air on a special edition of ABC's 20/20 this Tuesday: 'The same thing that happened to my daughter is what happened to Whitney.'

Bobbi Kristina was found in her bathtub almost three years to the date that her mother was pronounced dead after suffering a similar fate while staying at the Beverly Hilton for the 2012 Grammy Awards.

Houston was pronounced dead on the scene after being discovered in the bathtub of her suite at the hotel, with accidental drowning, heart disease and cocaine use later cited as the causes of death.

The Fulton County Medical Examiner's report for Bobbi Kristina revealed that her death was caused by 'immersion of face in water complicating mixed drug intoxication'.

Brown also discusses his turbulent relationship with Houston in the interview, including the drug usage that would later play a role in her death. 

'That was the first time I saw her do drugs,' says Brown in a preview for the interview.

'Cocaine?' asks Roberts, to which Brown replies; 'Yes ma'am.'

He later says of his life after divorcing Whitney in 2007: 'I came into the marriage with money, and I left the marriage with nothing.'

Bobbi Kristina was just 14 at the time of her parents divorce, and five years later she became the sole beneficiary of her mother's multi-million fortune after Houston's death.

Love: Bobbi Kristina became engaged to Nick Gordon just eight months after inheriting all of her mother's multi-million-dollar fortune following her death (couple above in October 2012)

Memories: Brown will also talk about his 14-year marriage to Houston, and detail his ex-wife's drug use in the interview (above)

It was eight months after her mother's tragic passing that Bobbi Kristina announced she was engaged to Nick Gordon, who was raised at times during his childhood by Houston and who many considered to be a brother-like figure to Bobbi Kristina.

The pair later claimed they had been married in early 2014, but Brown shot down those statements, saying the two had yet to wed.

It was Gordon who found Bobbi Kristina passed out in the bathtub at their Georgia townhouse, and in the months that followed some accused him of playing a role in his fiancee's death.

The chances of Gordon ever going to trial however decreased drastically following the release of Bobbi Kristina's autopsy report, in which the medical examiner said they could not tell for certain exactly how she died and if it was an accident or possible murder.

Gordon's lawyers have called on Fulton County District Attorney Paul Howard to publicly declare that Bobbi Kristina's death was not a murder, but so far he has refused to make this statement.  

It was also Gordon who tried to resuscitate Houston when she was found unresponsive in her bath-tub just hours before she was due to attend Clive Davis' annual Grammy party. 

Mourning: Brown attends Bobbi Kristina's funeral at St. James United Methodist Church in Georgia last August (above)

Dad: Brown is expecting a new baby with his wife Alicia Etheredge (above), the couple's third child

Brown meanwhile is preparing for a more joyful event these days - the birth of his new child with wife Alicia Etheredge.

The bundle of joy is set to arrive right around the same time Brown's memoir, Every Little Step, hits bookshelves this month.

The couple was married in 2012 and also have a son Cassius, seven, and daughter Bodhi, who will celebrate her first birthday in July. 

Brown's new family seems to be the biggest help to him during these difficult times, as he tells Roberts in his interview: 'I thank God I'm still here.'