United Kingdom, Feb. 20 -- Sir Mick Jagger's eight-year-old son has been left on crutches after sustaining a leg injury.

The Rolling Stones frontman's boy Deveraux has his left limb in a blue cast and is using mobility aids after being involved in a mystery incident, the rocker's partner Melanie Hamrick has revealed.

Melanie took to her Instagram Story to show a picture of her son's injured leg and admitted it was painful seeing the boy struggle.

She captioned her post: "Nothing feels more true - When they hurt you hurt (crying emoji) He'll be back playing football again in no time though!!"

It is unclear when or how Deveraux was injured, or if he is at home or being treated in hospital.

The 37-year-old former ballerina previously pr...