Writing time verses family life

I sometimes wonder how I will fit all that I need to do for me and my writing in amongst my family demands. I wonder at what point I should put my writing above those of my family, or do I write all morning and then spend the afternoon trying to get the home straight? Would it work better the other way round? Get the family things done first and then write? When I've tried it this way round the family demands take over and I don't get any writing time! Finding the balance sometimes seems too much and what normally suffers is my writing!