This call-up is the culmination of his outstanding achievements for Brighton College, where he is now studying for A levels, as well as Sussex and the London and South East division teams.
Chisholm started his rugby at Haywards Heath RFC at the age of seven and was part of a hugely successful squad. He travelled to Australia last summer with Sussex and represented the London and South East at U16 level.
While at Warden Park he was deputy headboy and played in all the school teams, representing Sussex Schools at rugby union, athletics, cricket and swimming. He swam in two national finals with his school team and was placed in two South East 200m finals.
He has been with Harlequins since he was 14 and now hopes to enjoy a memorable experience with the England squad and follow in the illustrious footsteps of former Warden Park student Roy Winters, who also represented his country at under 18 level and went on to play for the full England team.