Conversation so far:
What can you tell me about the Family relations of Nightcrawler?
Mystique was indeed comics, Nightcrawler's biological mother.
How was Mystique being Nightcrawler's mother confirmed?
Mystique being Nightcrawler's biological mother was confirmed by writer Scott Lobdell in X-Men Unlimited #4.

Question: what else did he find out about family?
Self-contained rewrite: What else is there about Nightcrawler's family besides Mystique being his biological mother?