Want to know who you really are? Take an at-home DNA test, just like over 26 million others have around the globe. But the question is: why? For many, it’s just a bit of fun; for others it might be for medical insight. But for everyone, it promises to tell you who you really are – and for many, those results might come as a surprise. For BBC reporter Sophia Smith Galer and her father, an innocent at-home kit led to a series of shocking discoveries about their family