Kate Osamor wrote to a judge asking for leniency for her son, Ishmael Osamor, who was caught with drugs

Bestival is perhaps Britain’s most eclectic summer music festival — an array of popular musicians playing in the grounds of an old English castle.

Flags flew around the festival site at Lulworth Castle, Dorset, last year as bands including the XX and the Pet Shop Boys headlined on the main stage.

On the second of four days, security staff noticed two men near an art installation and suspected a drug deal. The guards challenged the men, who fled.

One escaped but the other was caught. He was Ishmael Osamor, then 28, the son of Kate Osamor, the shadow international development secretary. He was carrying drugs that prosecutors said were worth up to £2,500.

The haul included about 250 pills of Ecstasy, 5.7g of ketamine, a