how to remove property from javascript object without removing code example

Example 1: javascript remove property from object

var person = {"first_name": "Billy","last_name": "Johnson"};
delete person.last_name; //delete last_name property

Example 2: how to remove property of object in javascript without delete

const names = {
  father: "Johnny",
  brother: "Billy",
  sister: "Sandy"
}

const newNames = Object.keys(names).reduce((object, key) => {
  if (key !== "father") {
    object[key] = names[key]
  }
  return object
}, {})

// { brother: "Billy", sister: "Sandy" }