On theatre days I eat lunch at 4. Now my 7 year old says she's 'not hungry' at 1

Holidays, so she's at home with our caregiver and calls me at lunchtime. Yesterday she said she'll eat 'later, like Mumma on operation days'. Turns out this has happened three or four times this month, and Didi has been keeping her plate aside till 3. My hours aren't changing any time soon. How do I sort this out without making a big speech about it? When I tried, she said 'but you also don't eat'. Fair point, beta 🙂