"We have a water bottle like that at our house!" she said.
"Do you?" I replied, "We have two. A red one and a purple one." I grabbed both to show her.
"Oh! Is the purple one for you, and the red one for... [realizes she doesn't know Josh's name]... your daddy?"
"Um... [Not sure what the right answer is here, had to decide whether to explain the difference between 'husband' and 'daddy']... Yes!"
To a three year old in a loving, two-parent home, "Daddy" = "Male head-of-household," regardless of the presence of children. It made me smile.