The Last Coal Barge

When Danny loses his dog, Skip, on the site of the old Pit, he's worried that Skip has gone down a rabbit hole and will die if he can't find him.
Luckily, a stranger, Jarrad Turner, a boy Danny doesn't know, rescues Skip.
Jarrad has two unusual pets of his own - a pony and a blackbird which cause Danny some anxiety.
Jarrad insists he lives at Lock Cottage but Danny knows the Carters live there. Is there a mystery about Jarrad Turner? Does Danny's Grandad know anything about him?
THE LAST COAL BARGE is now a sunken wreck in the deep water of the Pit's old coal loading bay.
What has happened to Jarrad in the past?
How does Danny's Grandad know him?