Was there any difference of opinion between Charles Darwin and his Father in law Josiah Wedgewood?

If you'll recall, Charles Darwin was a bit reticent to publish his findings for quite some time. Although he evidently developed his theory of evolution shortly after the voyage of the Beagle, when he was a young man, he delayed publishing his book, Origin of Species, until he was pretty old, because he knew it would cause a furor among pious Christians, who would see it as an attack on their religion. When he did finally publish it, he left out the final portion, which he later published separately under the title, The Descent of Man. In this book he laid out the thesis that people too are essentially animals and also evolved. If people evolved and are related to such primates as chimpanzees, gorillas, and even monkeys, how much more closely must we all be related to one another, regardless of skin color? Now I am not aware of Darwin himself making any statements about slavery or racism, per se, but this follows logically and he was an eminently logical man. He seems most unlikely to have accepted the ridiculous notion that dark-skinned people were not fully human simply because their skin was not as pale as his own, as so many Victorian-era Englishmen did. He was far too good a scientist for that. He might not have expressed the sentiment as eloquently as Josiah Wedgewood and said, "the slave is my brother," but he practically said that chimpanzees were our cousins, so I'm pretty sure he thought the same way as his father-in-law. Also, despite all the vilification that poor old Darwin gets from fundamentalists to this day, he was actually a very pious Christian himself.