Quick Question!

My friend has just started on CD but she ate a big dinner yesterday and the day before. Will she gain? I've told her not to, i've completed my first week and I don't miss food now!

how big a dinner did she eat? If its her first week and she only had one meal with the shakes she probably wont put on because she is unlikely to be taking in more calories than she needs, but she also wont be losing the water you normally lose in the first week so she may either STS or have a very small week one loss.

Why is she having the meals, would she be having low carb meals? or normal dinners?

She said she was craving food.

This diet is mainly successful if you stick to the plan. If she is regularly going well off plan then its a waste. I think the best she can hope for is a STS.
May be worth having a good talk to her. If she wants to eat then go on a CD food plan.

I think it might be worth her talking to her CDC about doing a higher plan, she obviously does not have the mindset for SS right now, and she is just wasting her money and energies if she is just going to stick to it during the day and the ignore it in the evenings

Maybe when she has her first weigh in she will realise that this is not going to work for her this way.