Billie Eilish has said that living with Tourette’s syndrome is “very exhausting.” The 20 -year-old pop star suffers from the condition which causes individuals to make sudden twitches or repeat certain sounds and claimed that while her tics are un-noticeable to most people, they will occur if she is filmed long enough. She said: “If you film me for long enough, you’re going to see lots of tics. These are things you would never notice if you’re just having a conversation with me but for me, they’re very exhausting.” The ‘Happier than Ever’ hitmaker went on to explain that while she “loves” talk…