As I remember, German Aldi's split into Aldi Nord/North and Aldi Sud/South between the two brothers that owned the firm, over a conflict on cigarette sales.
If I am correct, U.S. Aldi's is owned by Aldi North; Trader Joe's is owned by Aldi South.
"The business was split into two separate groups in 1960, that later became Aldi Nord, headquartered in Essen, and Aldi Süd, headquartered in Mülheim...
"Internationally, Aldi Nord operates in Belgium, Netherlands, France, Luxembourg, Poland, Portugal and Spain, while Aldi Süd operates in Australia, Austria, China, Hungary, Ireland, Italy, Slovenia, Switzerland, United Kingdom and United States...
"Aldi Nord also owns the Trader Joe's grocery chain in the United States which operates separately from the group."
If I am correct, U.S. Aldi's is owned by Aldi North; Trader Joe's is owned by Aldi South.
"The business was split into two separate groups in 1960, that later became Aldi Nord, headquartered in Essen, and Aldi Süd, headquartered in Mülheim...
"Internationally, Aldi Nord operates in Belgium, Netherlands, France, Luxembourg, Poland, Portugal and Spain, while Aldi Süd operates in Australia, Austria, China, Hungary, Ireland, Italy, Slovenia, Switzerland, United Kingdom and United States...
"Aldi Nord also owns the Trader Joe's grocery chain in the United States which operates separately from the group."
https://en.wikipedia.org/wiki/Aldi
EDIT: In the U.S., Aldi Nord owns Trader Joe's, and Aldi Sud owns the eponymous grocery chain.