So far, I have found three advice columns for parents from the 1930s and 1940s.
The earliest was from the January 7 1932 Toronto Daily Star:
I couldn’t find out much about Mrs. Gladys Huntington Bevans, other than that she (probably) lived from 1882 to 1947, and was the author of the 1930 pamphlet A Group of Simple and Beautiful Prayers and Graces for Children.
The next one is from the November 27 1936 edition of the Toronto Globe and Mail:
Angelo Patri (1876-1965) was a New York City school principal, syndicated columnist, and author. He wrote a number of books intended for adults, and some Pinocchio books for children. There is now a New York middle school named after him.
And, lastly, here’s a column from the February 8 1945 Toronto Daily Star:
Myrtle Meyer Eldred (1885-1978) started her newspaper column in 1918. A collection of her columns was published in 1931 and reprinted in 1951. One writer claimed that Ms. Eldred tended to think that all babies should be treated exactly alike, which is probably a bad thing.