Thanks K_Chan. Last Dec. when I visited Taiping Lake Gardens, I only managed to see a pair of Oriental Pied Hornbills; the encounter of this family of Rhinoceros Hornbills this time was a big surprise, in particular the young one !
Regarding birding at Penang, I used to visit Air Hitam Dalam Educational Forest. You can google it for the exact location. These days it's easy to get there by hiring a 'Grabcar'. However, the route provided by Grab would lead the car to somewhere close to the rear carpark without any signal and proper driveway. Therefore you should tell the driver you want to go to the front carpark (near the reception office) accessible from the main road.