Until DD was about three she had dinner by 5:30pm. As a baby I would do the bath and bed time routine after that and she would go down for the night (not to say she didn't wake up, but that was bed time). As a toddler, she was always hungry in the late afternoon and I didn't see the point in giving her two 'meals', or keeping her up later. Even now, she'll wolf down a decent sized snack when she gets home from preschool and will sometimes eat hardly any dinner at 7pm-ish (DP cooks, so we wait for him).

I used to save leftovers from the night before and that's what I'd give DD for dinner at 5pm. Saved extra cooking!