Congratulations! Both my parents come from families of 7 kids, and big families are so much fun!

People just say those things because of ignorance and they have nothing better to say. Perhaps just point out 'oh we don't view children as a burden, we see them as a blessing, so we feel really lucky to be expecting another!'

So 'oh you'll have your hands full!' Say, 'yes, we're really looking forward to it' - or a favourite of mine 'we'd rather full hands over empty hands any day'.

All the best with your pregnancy, people have been having large families for many many years! (perhaps point that out too :P)