| A | B |
| King George | Grandfather's parrot |
| Polly | serving girl at the Cook Coffeehouse |
| Mattie's father | a carpenter by trade |
| Carris | believes that bad coffee caused people to get sick |
| Bowles | in charge of the orphan house |
| Eplers | German immigrants who sell eggs at the market |
| Rowley | not a real doctor but prescribes medications |
| Silas | Mattie's cat |
| William Farnsworth Cook | Grandfather |
| Nathaniel Benson | painter's assistant |
| Pernilla Ogilvie | pompous, rich woman |
| Colette Ogilvie | engaged to Roger Garthing |
| Jeannine Ogilvie | the youngest daughter |
| Flagg | cares for Mattie at Bush Hill |
| Lucille | Mattie's mother |
| Eliza | born a slave |
| Mattie | age 14; has big dreams for the future |
| Deveze | pronounces Mattie is recovering |
| Brown | runs a print shop |
| Kerr | diagnoses Mother with yellow fever |
| Barrett | apothecary |
| Nell | cared for by Mattie |
| Gundy sisters | cared for by Eliza |
| Joseph | a cooper; Eliza's brother |
| Robert and William | Joseph's children |
| Mother Smith | elderly woman who cares for Joseph and his children |
| Sharp | raged through his house before he died |
| Benjamin Rush | His followers believed that yellow fever victims should be bled. |
| potter's field | held mass graves for the fever victims |
| Blanchard | flew a hot-air balloon |
| Peale | a famous portrait painter |
| Richard Allen | founded the African Methodist Episcopal Church |
| Absalom Jones | first African-American to be ordained an Episcopal priest |
| Stephen Girard | supervised the transformation of Bush Hill into a hospital |
| Bush Hill | site of a hospital for yellow fever victims |
| High Street | Market Street |
| Matthew Clarkson | Philadelphia mayor |