The leaders are debating the issue of North Sea Oil.
Alex Salmond says that "every other country in Europe would give their back teeth to have North Sea Oil".
Alistair Darling argues that it is risky to rely on a source of revenue that is very volatile, saying that Salmond is "gambling our children's future".
More top news
A look ahead at the forecast for the Border region.
His father, Secretary of State for Scotland David Mundell, is one of the highest profile Remain supporters north of the border.
The company that owns a Cumbrian nursing home has been fined £400,000 after a 91-year-old woman died after falling from her bed.