"It is with great sadness after a five-year battle to multiple myeloma cancer our loving father Martin Brown passed away age 63 peacefully yesterday," she wrote in a message also on behalf of her sister, Danielle.
"Both of us, his children, were by his side and would like to say thank you to St Gemma's and all the doctors and nurses for their amazing care and support over the years," the 41-year-old former Spice Girl continued. "Please respect our privacy and let us as a united family grieve. With love and respect. Melanie and Danielle Brown. Be Free Dad."