Poldark Saga - Winston Graham discussion

Valentine suffered from rickets, which is caused by a vitamin D deficiency in childhood. That's really not all that surprising since he probably didn't get outside in the sunshine as much as other children. Had he spent more time at Trenwith, he probably wouldn't have developed the condition, but he spent a fair bit of time in the city without the benefit of running around a countryside estate as Geoffrey Charles had been able to do.