In Batman v Superman: Dawn of Justice, the major conflict between Superman and Batman ended after Batman got to know about Superman's mother's name:
Batman: [suffocating Superman with his foot on his throat] You were never a god. You were never even a man!
Superman: [hardly breathing] You're letting them kill Martha...
Batman: What does that mean? Why did you say that name?
Superman: Find him... Save Martha...
Batman: Why did you say that name? Martha? Why did you say that name? WHY DID YOU SAY THAT NAME?
Lois Lane: [enters running] It's his mother's name! It's his mother's name. src
This made Batman stop harming Superman and rethink his actions. But before this film I never realised that both superhero's mothers have the same first name - Martha Kent and Martha Wayne. Is it just a random coincidence that their mother's share same name, or is one character inspired by the other, or is this a reference to some other work?