Can you get a short term loan?

my boyfriend and i are looking to buy a house, we have been approved for a mortgage and are waiting for my boyfriends family home to sell, as we are getting the deposit from that, but if we see a house we like in the meantime is it possible to obtain a short term loan from a bank to cover the deposit? we'd be looking at around 6 months for the house to sell, and for all the monies to be handed over etc and dont want to miss out on a house in the meantime