If most of the plants solar panels (leaves) have been consumed then there will be no energy available to adequately form sprouts. The most important thing was your grandson having a ball with the plant and pest.

And even if sprouts did form they would be full of caterpillar frass.

Thank you both for replying. Just as I thought, will try harder next year. Netting springs to mind!

Mine are the same but we have picked off all the caterpillars (I hope) and covered the plants with net -wish we had though to do that before).As no sprouts have formed yet and the caterpillars were very small and fairly newly hatched we are pressing on hoping for the best.I'm hoping that the plants will now continue to grow as normal.If you throw them out you certainly won't get any sprouts but as long as haven't already formed you stand more chance than if you give up now.

Thank you. I think I will just let them be and see what happens. I had little mesh cages on them from the start but the plants grew too tall so had to remove them. I am feeling rather silly as well as mad at myself. :{