Is Your Sister Hot

Yesterday, just before leaving work, I heard a ruckus on the other side of the office. Passing by there on my way out the door I discovered it was WeZ and Stilks debating whether it is possible for a guy to tell whether his sister is hot or not. Stilks says not but WeZ and the others around them all said it was possible. Liv was there to give a female perspective and sided with the others. Stilks seems to think that it is unnatural to even consider whether your sibling is hot or not. I think it is quite possible for anyone to recognise and acknowledge the beauty and sexiness of a sibling, or even a parent or child, without actually feeling sexual attraction towards them. What do you think?