Parent.js

import React, {Component, Fragment} from 'react';
import BigBrother from './BigBrother';
import LittleSister from './LittleSister';
import LittleBrother from './LittleBrother';

export default class Parent extends Component{
    /****
    A component with a render prop takes a function
    that returns a React element and calls it 
    instead of implementing its own render logic.
    A common practice is to call it render but the prop
    can be whatever you want.
    ****/
    
    render(){
        return (
            <Fragment>
                <BigBrother copycat={ (brother) => (
                    <Fragment>
                        <LittleSister bgcolor="pink" brother={brother}  />
                        <LittleBrother bgcolor="skyblue" brother={brother} />
                    </Fragment>
                )}/>
            </Fragment>
        );
    }
}