How can I execute a function from parent?

// Parent
function Parent () {
  let something;

  return (
    <Child something={something}/>
  )
}

// Child
function Child(props) {
  props.something = () => console.log("hello");

  return <div>Hello</div>
}

// Parent
function Parent () {
  let something;

  return (
    <Child something={something}/>
  )
}

// Child
function Child(props) {
  props.something = () => console.log("hello");

  return <div>Hello</div>
}