By Ben Weissmann
Answer: INITIAL THREAT

The first step of the puzzle is to use the information provided to construct a family tree. The information is sufficient to both construct relationship and relative age, so we arrive at this family tree of the five mothers and their daughters, ordered from oldest to youngest:

  • Tiffany
    • Heather
    • Eleanora
    • Yentl
    • Angelina
    • Rosemarie
  • Elaine
    • Sandra
  • Ulliviera
    • Claire
    • Harriett
    • Sebastiana
    • Allison
  • Ursulandina
    • Clementina
    • Yevgeniya
    • Leslie
    • Annalise
  • Daniella
    • Isabel
    • Evelina
    • Selina

Additionally, each family member’s description mentions one or more food items, and all of the children’s descriptions include a numeral. Collating all of this information yields this tree:

  • Tiffany—chicken
    • Heather (3)—cream
    • Eleanora (2)—onion
    • Yentl (2)—white wine, shallots
    • Angelina (1)—egg yolks, mushroom, lemon
    • Rosemarie (1)—egg yolks, cream
  • Elaine—tomato
    • Sandra (2)—onion, celery, bell peppers
  • Ulliviera—veal
    • Claire (4)—mustard, wine
    • Harriett (7)—mushrooms, shallots
    • Sebastiana (9)—red wine, bone marrow
    • Allison (2)—madeira
  • Ursulandina—egg yolk, butter
    • Clementina (1)—cream
    • Yevgeniya (6)—vinegar, tarragon
    • Leslie (1)—tomato
    • Annalise (2)—orange
  • Daniella—milk
    • Isabel (3)—gruyère
    • Evelina (2)—onion
    • Selina (1)—crawfish

Reading the first letters of the names in the order they’re presented here yields the hint THEY ARE SUCH SAUCY LADIES. As clued by the hint, the title, and the general food theme, each of these characters corresponds to a classic French sauce. The five mothers are the five mother sauces of French cuisine, and the children are daughter sauces—variants of those mother sauces.

Each character can be matched with a coresponding sauce based on their position in the family tree and the ingredients provided. As an additional confirmation, the number of letters in each character’s name is the same as the number of characters in the name of the sauce:

  • Velouté—chicken
    • Suprême (3)—cream
    • Bretonne (2)—onion
    • Bercy (2)—white wine, shallots
    • Poulette (1)—egg yolks, mushroom, lemon
    • Allemande (1)—egg yolks, cream
  • Tomate—tomato
    • Creole (2)—onion, celery, bell peppers
  • Espagnole—veal
    • Robert (4)—mustard, wine
    • Chasseur (7)—mushrooms, shallots
    • Bordelaise (9)—red wine, bone marrow
    • Madeira (2)—madeira
  • Hollandaise—egg yolk, butter
    • Mousseline (1)—cream
    • Béarnaise (6)—vinegar, tarragon
    • Choron (1)—tomato
    • Maltaise (2)—orange
  • Béchamel—milk
    • Mornay (3)—gruyère
    • Soubise (2)—onion
    • Nantua (1)—crawfish

Using the numbers of the daughter sauces as indexes into the sauce name yields the request PREPARE US A MACARON. Teams which successfully follow that instruction are given in exchange the final answer, INITIAL THREAT.