She died in Paris.

Born in NYC, she went to the Parsons School of Design and lived in or near Monaco.

She also illustrated Robert K. Smith's 1972 "Chocolate Fever."

I only found the death notice by including her son's name.

https://www-dansnoscoeurs-fr.translate.goog/gioia-caputo/3516905?_x_tr_sl=fr&_x_tr_tl=en&_x_tr_hl=en&_x_tr_pto=sc
(translation)

Paris (15th).
Mr. and Mrs. Jean-Guy Caputo and their children, Mr. and Mrs. Marco Caputo, their children and grandchildren, Mr. and Mrs. Georges Caputo and their children
are sad to announce the death of
Mrs. Gioia CAPUTO née Fiammenghi,
died on October 13, 2021, at the age of 92, in Paris.
The religious ceremony will be celebrated in the Saint-Pierre-de-Montrouge church, in Paris (14th), on Saturday October 16, 2021, at 11 a.m.
____________________________________________________________

What I posted in 2019, with added videos:

http://images.google.com/images?hl=en&q=Fiammenghi%20gioia&um=1&ie=UTF-8&sa=N&tab=wi
(book covers)

http://www.lib.usm.edu/legacy/degrum/public_html/html/research/findaids/fiammenghi.htm
(partial booklist, with authors, & brief bio)
Excerpt:

"Gioia Fiammenghi was born on September 29, 1929 in New York City to a family with a long history of artistic accomplishment. She received a scholarship from Parsons School of Design and graduated in 1950. She worked briefly as a fashion model and an assistant art director before becoming a free-lance artist and illustrator in 1951. She married Guido Caputo in 1959 and had three children. She has lived much of her adult life in Europe, illustrating books for American and European publishers."

https://www.google.com/search?ei=pxiRXbDZIYSY_Qbh1pOgDA&q=Gioia+Fiammenghi+kirkus&oq=Gioia+Fiammenghi+kirkus&gs_l=psy-ab.3...976.2148..2348...0.0..0.118.676.4j3......0....1..gws-wiz.......0i22i30j33i160.__6UkcqJwmo&ved=0ahUKEwjwyMrz8_bkAhUETN8KHWHrBMQQ4dUDCAo&uact=5
(two Kirkus reviews)
https://www.goodreads.com/author/list/105368.Gioia_Fiammenghi
(reader reviews; there are three pages of titles)

https://www.youtube.com/watch?v=kymz6Clso1w
(read-aloud of Teddy Slater's "Stay in Line" - the reading starts at 2:32. Btw, Marilyn Burns, who is mentioned, is the author of "The I Hate Mathematics! Book." The reading takes about 7 minutes.)

https://www.youtube.com/watch?app=desktop&v=X6vCgWcEWGk
(17:31 book report on Chocolate Fever - not sure if the pictures get shown - probably not)

WORKS (not complete, I think):

BELINDA S NEW SPRING HAT (1969)
BIGGER AND SMALLER (1971)
BIRTHDAY BOOK OF SIX (Undated)
BORN TO DANCE SAMBA (1984)
BURRHEAD S CONFESSIONS (1960)
THE DAY JEAN PIERRE WENT ROUND THE WORLD (1965)
THE DAY THE TV BLEW UP (1988)
GUS ET LE CAMBRIOLEUR (1985)
GUS ET LE HINDOUS (1982)
HOW TO FIGHT A GIRL (1987)
HUGO THE HUGE (1968)
THE IGUANA S TAIL (1969)
LIBRARIES
LITTLE RACOON AND THE OUTSIDE WORLD(1965)
MONKEY GROWS UP (1991)
MRS. ARRIS GOES TO PARLIAMENT (1958)
MRS. ARRIS GOES TO PARIS (1958)
MYSTERY OF THE BLUE NETS (1957)
NOISY NANCY NORRIS (1965)
AN OCCASIONAL COW (1989)
ONCE UPON A HOLIDAY (1959)
ONCE UPON A SEASON (1962)
PAPA ALBERT (1964)
PINOCCHIO (1974)

P.J. CLOVER, PRIVATE EYE
THE CASE OF THE BORROWED BABY (1988)
THE CASE OF THE HALLOWEEN HOOT (1990)
THE MYSTERY OF THE MISSING MOUSE (1985)

SCOTT FOREMAN READING TEXTBOOK
SECOND GRADE DOG (1990)
SKIP AROUND THE WORLD (1957)
UN CHAT COMME MOI (Undated)