const Document = props => {
  console.log(JSON.stringify(props));
  return(
    <div className="row">
      <div className="col-3">{props.dateOnLetter}</div>
      <div className="col-1">{props.personFrom.firstName}</div>
      <div className="col-1">{props.personFrom.lastName}</div>
      <div className="col-1">{props.personTo.firstName}</div>
      <div className="col-1">{props.personTo.lastName}</div>
    </div>
  );
};

{"dateOnLetter":"2012-04-23T18:25:43.511+0000","personFrom":{"id":"5b637d319e30ed3f8c322c64","firstName":"Georgexxx","lastName":"TheCatxxx"}}

<div className="col-1">{props.personTo.firstName}</div>

TypeError: Cannot read property 'firstName' of undefined - using 'props' in react

<div className="col-1">{props.personTo ? props.personTo.firstName : ""}</div>