The 3rd Viscount died on 10 January 2018 and the viscountcy became extinct on his death .
The titles were then held by his half - brother , Alan Brooke 's younger son , also named Alan .
The 3rd Viscount died on 10 January 2018 and the viscountcy became extinct on Alan Brooke 's death .
The titles were then held by his half - brother , Alan Brooke 's younger son , also named Alan .