Valuation and Division; or, Where is Perry?

Much of Douglass's genealogy appears in two documents that I have mentioned before. The first is the December 19, 1826, valuation list of the slaves in Aaron Anthony's estate. The second is the distribution list, dated September 17, 1827, showing the division of Douglass's extended family among the three Anthony heirs, Richard Anthony, Andrew Anthony, and Lucretia [Anthony] Auld's widower Thomas Auld.

Recently, I noticed details between these lists that literally did not add up. Perhaps because this involves math, I'm having difficulty puzzling it all out.

Here is the valuation list giving the name, age, and value of each of the family members:

1. Betty, 53 - $20
2. Harry, 40 - $275
3. Kate, 38 - $60
4. Milly, 37 - $100
5. Betty, 26 - $200
6. Arianna, 25 - $200
7. Mary, 22 - $200
8. Hester and child, 17 - $220 [my guess: $200 for her and $20 for the child]
9. Perry, 14 - $160
10. Jerry, 14 - $180
11. Sarah, 13 - $135
12. Tom, 13 - $160
13. Phill, 12 - $150
14. Eliza, 11 - $120
15. Prissa, 11 - $120
16. Henny, 11 - $50
17. Frederick, 9 - $110 (marginal note on document: "later known as Fredk Douglass")
18. Nancy, 9 - $90
19. Henry, 7 - $85
20. Kitty, 7 - $70
21. Stephen, 8 - $100
22. William, 5 - $75
23. Arianna, 5 - $5
24. Caroline, 2 - $25
25. Angelina, 2 - $25
26. Maria, 1 - $20
27. Harriott, 1 - $10
28. Charles, 5 - $70
29. Tom, 2 - $30

Neither this list nor the distribution list give any clues to the relationships among these slaves, although other documents do.

Here is the distribution, with each heir receiving slave property valued at $935. I've added in their ages and values:

Andrew S. Anthony:

1. Betty, 53 = $20
2. Young Betty, 26 = $200
3. Stephen, 8 = $100
4. Angelina, 2 = $25
5. Jerry, 14 = $180
6. Sarah, 13 = $130
7. Kitty, 7 = $70
8. Little Arianna, 5 = $5
9. Caroline, 2 = $25

Total: $755 -- $180 short of $935

Thomas Auld:

1. Negro Milly, 37 = $100; and infant [not identified, apparently included in her valuation]
2. Tom, 13 = $160
3. Nancy, 9 = $90
4. Henny, 11 = $50
5. Harriott, 1 = $10
6. Frederic, 9 = $110
7. William, 5 = $75
8. Hester and child, 17 and [unknown] = $220
9. Eliza, 11 = $120

Total: $935 - matches with the total on the division

Richard Anthony:

1. Arianna, 25 = $200
2. Maria, 1 = $20
3. Harry, 40 = $275
4. Prissa, 11 = $120
5. Kate and child, 35 and [unknown] = $60
6. Phill, 12 = $150
7. Henry, 7 = $85

Total: $910 - $25 short of $935

Notice that Charles, Frederick's brother Perry, Mary, and the 2 year old Tom do not appear in the division. At first I thought that Mary may have been Maria, but at $200, she puts that group over $935. I thought perhaps that the 2-year old Tom might be included as Kate's child. At $30 he fits, but put them over by $5. I also thought that Charles or Tom might be Hester's child, but Auld's list adds up, and her child was included with her on the valuation list, while Charles and Tom were valued separately.

So, what am I missing? What are the documents missing?