Conversation so far:
How many children did Carl Nielsen have?
Carl Nielsen had five children, two of them illegitimate.
What were Carl Nielsen's five children names?
Carl Nielsen's children were called Carl August Nielsen, Rachel Siegmann, Irmelin Nielsen,  Anne Marie Nielsen and Hans Børge Nielsen.
Who did Carl Nielsen marry?
Carl Nielson married Anne Marie Brodersen.
What year did Anne Marie Brodersen and Carl Nielsen get married?
Carl Nielsen and Anne Marie Brodersen toured Italy together and married in St Mark's English Church, Florence, on 10 May 1891.
Are there any other interesting aspects about the Carl Nielsen article?
Shortly after arriving in Paris in early March 1891 Carl Nielsen met the Danish sculptor Anne Marie Brodersen, who was also travelling on a scholarship.
What was the name of the Danish sculpture Carl Nielsen met in Paris?
Carl Nielsen met the Danish sculpture Anne Marie Brodersen shortly after arriving in Paris in early March 1891.
Where did Carl Nielsen and Anne Marie Brodersen stay at?
Carl Nielsen and Anne Marie Brodersen toured Italy together.

Question: When did they return to Denmark?
Self-contained rewrite: When did Carl Nielsen and Anne Marie Brodersen return to Denmark?