Angela McGlynn, who lost her four-year-old son John Paul Massey in 2009 when his uncle's dog attacked him, has said parents cannot "just rely on the Government" to prevent future dangerous dog attacks.
Ms McGlynn has renewed her calls for all dogs to be muzzled around children under 12.
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Her comments follow the tragic death of Lexi Branson, who died in hospital after being attacked by her family's new pet dog at her home in Mountsorrel, Leicestershire, despite her mother Jodi Hudson's attempts to save her.
Lexi Hudson was named locally as the child who died in a dog attack in Mountsorrel
Ms McGlynn said Lexi Branson's death had raised painful memories.
"It brings everything back - straight back to day one all over again," she told ITV Daybreak.
"I would like to send out my sincere sympathies to Lexi's family because I know exactly what they are going through."
The dog was the family's pet and had been brought from a rescue home, according to neighbours.
Police said the animal died shortly after the attack which happened just after noon yesterday in Rowena Court in the town of Mountsorrell, between Loughborough and Leicester.