Ms Bashiran Bibi, 59, and her son Abdul Rahim, 36 (right), presenting a 1.3m by 1.8m national flag which she hand-knitted to President Tony Tan Keng Yam and his wife, Mary, at the Istana Open House yesterday. They were among more than 16,000 visitors at the Istana, which was open to the public in celebration of National Day. Visitors were treated to musical performances, balloon sculpturing and a guided tour of the Istana main building, among other activities. Also held yesterday was the Istana Art Event which is an annual community outreach programme organised by the Singapore Art Museum in conjunction with the open house.