Error while inserting the feedItem in Salesforce

I want to insert the feedItem.

List<FeedItem> fd= [select body from feedItem where parentId='5007F0000018WrE'];
List<FeedItem> it = new List<FeedItem>();
for(feedItem sa:fd){
FeedItem f1=new feedItem(body=sa.body, parentid='5007F000002ATW0');
it.add(f1);

}
insert it;

it is showing the following exception-

System.DmlException: Insert failed. First exception on row 1; first error: REQUIRED_FIELD_MISSING, Required fields are missing: [Body]: [Body]