Is it possible to use `if … in` to search through an object without it being case-sensitive?

If I want to get a value from the object know but the case is different, it won’t match: "Hello" won’t match "hello". Is there another work around for this?

function ct(e) {
  var know = {
    "Hi": "Hello",
    "How are you?": "Great",
    "Bye": "Have A Nice Day !",
    "Hello": "Hi , Whats Up",
    "What's your name?": "Claire Rachael"
  };
  let t = document.createElement("span");
  
  t.setAttribute("class", "chatMessage left");
  
  if (e in know) {
    setTimeout(() => {
      t.textContent = "Typing...";
      d.appendChild(t);
      g = d.getAttribute("data-bottom")
        ? d.getAttribute("data-bottom")
        : 0;
      
      if (parseInt(g) < 200)
        d.scrollTo(0, d.scrollHeight);
    }, 2000);
    setTimeout(() => {
      t.textContent = know[e];
      d.appendChild(t);
      g = d.getAttribute("data-bottom")
        ? d.getAttribute("data-bottom")
        : 0;
      
      if (parseInt(g) < 200)
        d.scrollTo(0, d.scrollHeight);
      else
        alert("new message");
    }, 6000)
  }
  else {
    t.textContent = "I don't understand";
    d.appendChild(t);
  }
}