But it suddenly attacked Charlotte, leaving bite marks around her nose and eyes, before a chef managed to pull it away.
Charlotte’s nanny, who was supervising her along with her twin Henry and brother Callum, nine — called Mari to warn her.
But Mari was shocked at her shaken daughter’s injuries when she returned home — and likened them to slasher victims from the A Nightmare on Elm Street films.
She recalled: “She had blood and marks on her face. It was as if Freddy Krueger had run his knife fingers down her face. You could see how traumatised she was and the terror in her face. It was awful.
“She was shaking and her eyes were glazed. I’ve never seen a child so traumatised.
“How would you feel if a dog bit your face? She was only five.”
Mari cleaned Charlotte up in the bath but said her daughter has been left scarred and also undergoes counselling.
Mari, an HR executive from Maidenhead, said: “I phoned the non-emergency line to seek advice. She didn’t need any stitches but she goes and sees a counsellor regularly.”
It is understood the Sorry Seems To Be The Hardest Word star and David were in LA at the time of the attack in February 2016. But they are believed to have been told about it by staff days later.
However, Mari is furious at their failure to apologise personally or even call her.
She said: “I was quite shocked because it wasn’t an insignificant thing that happened.
“The dog didn’t just nip her, it bit her in the face and left scarring. I’m really upset there’s never been a phone call asking if there was anything they could do.”
The children had been friends at a £5,000 (A$8848) -a-term school. Mari said she saw Sir Elton and David — worth an estimated £100 million (A$176 million) — “on a number of occasions at the school” since the attack.
She added: “They absolutely did know about it. You can make assumptions but I don’t know why they didn’t apologise or ask how Charlotte was.
“It’s about responsibility as well, and being a responsible adult. I don’t care about status or celebrity.
“This is about everyday human decency and values and ethics. And when it comes to the crunch this is about a child. This was bad and it could have been far worse. If I had an animal and it turned on another person’s child I would have been mortified and gone out of my way to make sure the child was OK.”
She said she is not looking to take legal action but is speaking out now as Charlotte no longer goes to the same school as Sir Elton’s kids.
Mari added of her daughter, now seven: “She wanted to be a vet and was tactile as a little girl. But she is, as a consequence of what has happened, very, very wary of dogs.”
Sir Elton has three pet cocker spaniels, although it is not known which one bit Charlotte. He was given Arthur Dwight for his 56th birthday in 2003, and the pet was “best man” during his civil ceremony with David two years later.
Arthur even married his other spaniel Marilyn and the pair have a daughter Isobella.