I accidentally found Kiwi fruit was a good mover for my DDs

Other wise I used to stew apples or pears with some prunes and whizz it up when DD was really young. As she got older I would keep it in its stewed form and serve it as a treat, perhaps with some cream.

ETA: I just thought as a recipe, you could put the stewed fruit and prunes into triangles of puff pastry and bake them then eat hot for desert or cold the next day for a treat.