Edward Michael Hopton (left) and Guy William Hopton (right).
The paintings are usually listed on auction web sites as being sold as a pair.
Edward Michael Hopton (1884-1916), aged 5 or 6, and Guy William Hopton, aged 8 or 9 (1881-1915). They were the sons of Lieutenant General Sir Edward Hopton KCB DL JP and Clare Ellen Trafford. Both sons died during the Great War, Edward dying of pneumonia on service in Egypt and Guy killed in action on the Western Front.
The information in auction catalogues is sometimes unclear. One site titles the painting on the left as Portrait of a girl. The identification of the pictures given here is my interpretation of the information.