json - getParsedBody() - returns ''' in case of apostrophe present in the body || PHP || Slim

one text

While trying to parse the body which has an apostrophe in the content, I see the following being returned.

$request->getParsedBody(); -- returns &#39 for apostrophe;
json_decode($request->getBody(), true); -- returns correct readable character for apostrophe

Can someone please help me understand what's the difference here and which function is better to use ?