How to send data from Child to Parent with react?

Question

I have a a react Parent component which having a child component.

import Child from './child';
export default class Parent extends Component {
 constructor(props){
    super(props);
    this.state = {
     events: [
        {
          title: "My event",
          start: new Date(2019, 4, 27, 7, 0), // 10.00 AM
          end: new Date(2019, 4, 27, 14, 0) // 2.00 PM
        }
      ],
    }
 }
render() {
    return (
        <div> 
         <h1>Parent component</h1>
         <Child events={this.state.events}/>
       </div>);
} 

and on the Child component, I want to update this events and send it to Parent component.

How can I fix it ?