Stephen Belafonte tormented Mel B's family, saying they'd be cut off from her again ... according to Melanie's sister, who's now dancing on Stephen's metaphorical grave.
Danielle Brown says "8 years of abusive calls me and my mum have had stating we would never see Melanie again. I am laughing and celebrating as you were wrong. You are a sorry excuse of a man."
She also told Lorraine Giles -- the nanny Mel says Belafonte got pregnant -- to "rot in hell."
And perhaps best of all, Danielle quoted Beyonce in a parting shot at her sister's estranged husband -- "To the left to the left everything you own in the box to the left."