I have a friendly relationship with my boss, there's a line of professionalism but we chat on fb, follow each other on Instagram (she sent me the requests first) and get on really well. She just texted me to say colleague is leaving and how stressed she is (I'm on mat leave but return in three weeks). My job is part time, we needed someone in addition to me and colleague and now it's down to no-one until I'm back. I asked her what she's thinking and she said she'll hire someone else. As we needed someone else anyway (we need one full timer, two part timers and right now we only have me, a part timer), is there a way I could casually mention I'd like to become full-time? It'd be a little more responsibility but very similar to what I'm already doing.