What was the reason behind Stokes' folded finger gesture after match-winning knock?

RR all-rounder Ben Stokes' folded middle finger gesture after his match-winning knock against MI was a tribute to his father, Ged, who is suffering from brain cancer. Stokes' father had got part of his finger amputated instead of getting it operated to continue his rugby league career in 1980s as he couldn't afford to miss matches.