The young fan and his family who are now based in Hong Kong, were absolutely thrilled.
"Ok, so yesterday Sonny Bill Williams signed Coops autograph book and we were absolutely thrilled!!! Can I tell you what he did today... NZ lost to Fiji in HK 7's and after they collected their own runner up cups, the team walked past us and I called out to Sonny to have a selfie with us. Not only did he take the selfie, he gave Coops his runner up cup!!!! What a bloody legend," wrote Tan Guerin on Facebook.
Back at the 2015 Rugby World Cup final, Williams gave his winner medal to a young boy who was smoked in a tackle from a security guard after running on the field following the side's 34-17 win over Australia.
He also showed the world what it means to be a good sportsperson when he consoled devastated Springbok Jesse Kriel following their loss to the All Blacks in the Rugby World Cup semifinal.