A US website claimed that the 18-year-old was seen with "glassy" eyes at the New Jersey ceremony on Sunday (February 19) and "almost didn't make it" to see her mother laid to rest.
However, a source has since told Gossip Cop that the story is "absolutely not true" and Brown "was with family and friends the entire time".
The Houston family insider also pointed out that her glazed expression was the result of her crying over the loss of her mother.
Reports that Brown went missing after Houston's funeral on Saturday (February 18) and was found "getting high" have also been denied.
Footage of the service has been sold off to media outlets in order to raise more money for Brown.
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Watch Whitney Houston perform 'One Moment In Time' below: