Frederick F. Tisdall (1893-1949) was an important Canadian pediatrician. Tisdall served with the Canadian Army Medical Corps during the First World War, after which he served as a pediatric investigator at the Harriet Lane Home of the Johns Hopkins Hospital in Baltimore under the direction of Dr. Howland in 1920 and 1921. He joined the Hospital for Sick Children (now commonly known as SickKids) in Toronto in the winter of 1921 and in 1929 became the Director of the Nutritional Research Laboratories. In 1930 with Drs. Alan Brown and Theodore Drake, he developed the infant breakfast cereal Pablum, a nutritional breakthrough in the treatment of rickets by ensuring adequate Vitamin D in children’s diets. After Tisdall’s death, concerns were raised regarding his involvement in unethical nutritional research on First Nations communities.

Charles Widdrington Tinling was born on November 17, 1863, in Barbados, West Indies.

In 1877, he came to Canada, settling in Hamilton, Ontario, where he completed his education. He became a businessman and a president of the National Drug and Chemical Company of Canada (Ltd.), Montreal.

In 1888, he married Louise Brett Georgina Ryall (d. 1902) and in 1905, he married Mary Stuart Turner. He died on March 16, 1928, in Gibraltar while aboard the ss. Laurentic on a Mediterranean cruise.