Darling Whitledge (who was also her roommate in Hogwarts) and her should not only be friends but best friends! They are very similar in nature. Darling is established as being close friends with MJ's Jemima Greengrass (also same house and year) and Nicholes Octavia Fawley (same house but a year ahead of them) so if her and Darling are friends, those are potential connections too!