He said Maria had been at a family event following a bereavement, and had returned late at night to find the distressing scene.
Superintendent Gillian Mitchell, of Northumbria Police, said: 'At approximately 4.15 this morning we received a call to say that a small child had received a dog bite.
'Paramedics were called. Unfortunately, despite all their efforts, the child has died.
'Back at the house, there was a small terrier-type dog. That dog has been seized.
Obviously we have concerns about the care of the child.' Neighbours described Maria and Ryan as a 'caring couple in their 30s', who had owned the dog, Tricky, for about a year.
Others said they had previously seen the dog being chased by Mr Young after escaping over the couple's fence into the street.
One neighbour, who asked to remain anonymous, said: 'The dog is a Patterdale terrier and the family tend to keep it in the garden. It would get out from time to time and I would pick it up and throw it back in. It was no bother at all.
'I think the dog had become jealous of the baby and that is why this has happened. They have never had any bother with the dog in the past.
'It was Ryan's dog, as far as I'm aware. He is a lovely lad, a hardworking lad and an excellent father.He will be devastated.'
Another neighbour, Denise Haley, 59, said: 'Maria is a lovely girl and I simply do not know how she will cope with this tragedy. I'm scared of any dog but that dog seemed OK.'
A police car remained outside the couple's home yesterday and flowers had been laid outside the gate.
- Daily Mail