I know it's up to me. I have very weak self-discipline. But DH just keeps buying crisps and biscuits and ice cream. The house is always full of rubbishy treats. And though I ask him not to he just keeps on doing it, Not good for DS2 either, who is a bit chubby and unable for medical reasons to do much strenuous exercise for the next two years.
I'd love to hear from anyone who's found ways to just stick to their own diet plan no matter what the house is full of.