A mother elephant is leading her baby and two other youngsters to a waterhole. The one walking in the back is probably also hers while the little bull (you can see his little tusks already) could be her nephew.
One of Addo's big bulls taking a mud bath at the Hapoor waterhole. There are several reasons for throwing mud on their backs. Firstly elephants don't have sweat glands and throw mud and water onto their backs to cool down. Secondly because they have a lot of wrinkles in their skin, they have a lot of tics, lice and bacteria that live in those wrinkle. The mud hardens on top of the skin and it kills of all the unwanteds. Thirdly the mud also act as a protection against the sun. Now I understand why women like to have a mudpack on their face or go for a mud bath at a spa. Go figures.