Family, friends and fans continue to mourn the passing of Whitney Houston
NBC NATIONAL NEWS — As the investigation continues into Whitney Houston's death, so do preparations for her funeral Saturday in Newark, New Jersey.
Houston's musical roots were in gospel, and a member of one of gospel music's most prominent families, The Winans, will deliver the eulogy.
Gospel Grammy winner Marvin Winans is pastor at Perfecting Church in Detroit.
He presided over Houston's marriage to Bobby Brown in 1992.
Winans' siblings, Cece and Bebe, performed with Houston.
'When I heard Whitney was gone, I have to say, I was not surprised, because that's how close our families were,' Rev. Winans says.
But in addition to Houston's struggles, Winans also knew of her faith.
'We sang together, "I Go To The Rock" and it is the rock of salvation, that rock - that faith in Jesus that sustains us during times like this,' he says.
Meanwhile, in Los Angeles, the County Coroner's office has issued subpoenas to Houston's doctors and medical providers.
They're seeking pharmacy and medical records.
A standard procedure in death investigations.
Results of toxicology tests are still weeks away and will determine whether prescriptions drugs found in Houston's hotel room were a factor in her death.
Even with that question unanswered, the White House's drug czar says Houston's admitted struggles with substance abuse represent a teachable moment about the issue.
'When the CDC calls it a Public Health Epidemic, it's very clear we have to deal with this,' said Gil Kerlikowske.