The cubs are now seven months old and we've tracked their progress since they were small - well, smallish - 13-week-olds.

The sixth and final episode in our exclusive series - which you can watch above - shows how far Sinda and Bira have come since they took their first tentative steps earlier this year.

Instinct is now starting to take over as they progress from being cubs to 'proper big cats'.

They've shot up significantly in the last few weeks and, much to his disgust, are "almost as strong" as Richard Barnes, head of large carnivores at Port Lympne.

Parents Ingrid and Tug are letting their offsrping get on with it as they learn to stalk and catch things - and plans are afoot for even more additions to the park's tiger population.