Hale and Peter's or Hale's and Peter's?

Question

Quick questch. What is grammatically correct: I heard Hale and Peter's screeches. or: I heard Hale's and Peter's screeches.

Answer 1

When you are talking about something that belongs individually to each of them, both names get the apostrophe s. That is true in this case; each of them is screeching separately. If you are talking about something that belong to the two of them collectively, only the last name gets an apostrophe s. For example, I heard Hale and Peter's report on screech owls." They made one report together.

Answer 2

Hale's and Peter's screeches (they each have their own screeches)

Bob and Mary's car (they share the car)