The Dress of the Slaves, excerpts from this section, beginning p. 30: (From Nehemiah Adams, "The Southside View of Slavery" published 1854, being the report of a northern abolitionist and Christian pastor on traveling through the South for his health:

"To see slaves with broadcloth suits, well-fitting and nicely-ironed fine shirts, polished boots, gloves, umbrellas, for sunshades, the best of hats, their young men with their blue coats and bright buttons, in the latest style, white Marseilles vests, white pantaloons, brooches in their shirt bosoms, gold chains, elegant sticks, and some old men leaning on their ivory and silver-headed staves, as respectable in their attire as any who that day went to the house of God, was more than I was prepared to see. As to that group of them under the trees, had I been unseen, I would have followed my impulse to shake hands with the whole of them, as a vent to my pleasure in seeing slaves with all the bearing of respectable, dignified Christian gentlemen. As it was, I involuntarily lifted my hat to them, which was responded to by them with such smiles, uncovering of the head, and graceful salutations, that, scribe or Pharisee, I felt that I did love such greetings in the market-places from such people.

Then I fell into some reflections upon the philosophy of dress as a powerful means of securing respect, and thought how impossible it must soon become to treat with indignity men who respected themselves, as these men evidently did; nay, rather, how impossible it already was for masters who would so clothe their servants to treat them as cattle. Further acquaintance with that place satisfied me that this inference was right. There is one southern town, at least, where it would be morally as impossible for a good servant to be recklessly sold, or to be violently separated from his family, or to be abused with impunity, as in any town at the north."
And:
"But the women, the colored women, in the streets on the Sabbath, put my notions respecting the appearance of the slaves to utter discomfiture. At the north an elegantly-dressed colored woman excites mirth. Every northerner knows that this is painfully true. Gentlemen, ladies, boys, and girls never pass her without a feeling of the ludicrous; a feeling which is followed in some — would it were so in all — by compunction and shame. It was a pleasant paradox to find that where the colored people are not free, they have in many things the most liberty, and among them the liberty to dress handsomely, and be respected in it.

You do not see the tawdriness of color, the superfluity of yellow, the violations of taste in the dress of the colored women at the south to the degree which you observe in some other places. One reason, if not the chief is, they each have a mistress, a matron, or young lady, to advise and direct them, and to be responsible in
the community for their good appearance. They also wear fabrics and millinery which either good taste, or, at least, means superior to theirs, originally selected for the use of their mistresses and white members of the family. It may seem extravagant to some, but the pride we have in the respectable appearance of children is felt by southern mistresses with regard to their servants. A grotesque, ill-fashioned dress on a female servant appearing in public on the Sabbath, would be sure to be a subject of a hint from a neighbor or friend. My previous images of slaves were destroyed by the sight of those women with dresses which would have been creditable to the population of any town at the north. The most surprising sight of all, as an evidence of real refinement and good taste, was, here and there, a simple straw bonnet with a plain white ribbon, and a black silk dress. Such is the ordinary appearance of the women in a country town on the Sabbath, and indeed in the cities Fashion hardly stretches her influence further. Mixed with these specimens of the putting on of apparel are seen, of course, very plain, humble clothing and turban and instances of great neglect in dress."
As to children:
"Their attachments and sympathies are sometimes very touching. One little face I shall never forget, of a girl about seven years old, who passed us in the street on an errand, with such a peculiarly distressed yet gentle look, that I inquired her name. A lady with me said that she belonged to a white family, in which a son had recently killed a companion in a quarrel, and had fled. The natural anguish of a sister at some direful calamity in a house could not have been more strikingly portrayed than in that sweet little dark face. It had evidently settled there.

Going to meeting one Sabbath morning, a child, about eight years old, tripped along before me, with her hymn book and nicely-folded handkerchief in her hand, the flounces on her white dress very profuse, frilled ankles, light-colored boots, mohair mits, and sunshade, all showing that some fond heart and hand had bestowed great care upon her. Home and children came to mind. I thought of the feelings which that flower of the family perhaps occasioned. Is it the pastor's daughter? Is it the daughter of the lady whose garden I had walked in, but which bears no such plant as this? But my musings were interrupted by the child, who, on hearing footsteps behind, suddenly turned, and showed one of the blackest faces I ever saw. It was one of the thousands of intelligent, happy colored children, who on every Sabbath, in every southern town and city, make a northern visitor feel that some of his theoretical opinions at home, with regard to the actual condition of slavery, are much improved by practical views of it."

Towards the end of his book, and I'll repeat this often, Adams goes into the fact that Stowe's Uncle Tom's Cabin is as representative of the institution of slavery in the South, as the life of Robinson Crusoe was representative of a mariner's life.
I'll post more every so often, though you can access the book on Internet Archive.