Blandford died childless in 1703, and upon his father's death in 1722, the dukedom passed to his eldest sister, Lady Henrietta Godolphin (née Churchill).

After his father's creation, the younger Churchill, as heir apparent to the Dukedom of Marlborough, was awarded the title Marquess of Blandford.

[8] It was Blandford's personal wish to follow a military career as his father did, and join the latter's regiment, but his mother was concerned at the risks and wanted to ensure the dukedom could be passed through the male line.

By 19 February, word reached London that Blandford's condition was hopeless and the queen, who had lost seventeen children herself, wrote a heartfelt letter to the Duchess of Marlborough in which she stated that she prayed that "Jesus Christ comfort and support you under this terrible affliction, and it is mercy alone that can do it.

"[11] The Marlboroughs left Cambridge and settled in their country home in St Albans, in order to mourn the passing of their son and heir.