Pretend that I have a 10 year old son. He doesn't drink much water at school. So he usually has difficulties at poo.
I care about his health, so when I get home from work I often ask him
"Did you poo today?"
or
"Have you done a poo today?"
Which one should I use to care about his health rather than worrying he poo in bedroom?
I suppose the simple past is the one. Is it idiomatic? Does that sound natural?