Sorry to hear you were so upset today, especially when your DH is away. It can be very upsetting and frustrating when LOs appear not to be eating much. Please do take comfort in your own words though, "no child will starve themselves" - and especially she is not going to waste away in the time your DH is away.
Appetites can drop noticeably in toddlers and if it follows a growth spurt it is even more noticeable, their eating goes back to a "normal" amount but us parents have become used to the growth spurt amount so in comparison it can seem like they are living on fresh air.
You said yourself that she eats like a horse at breakfast and it is very common for toddlers to take in more of their calories in the morning and earlier hours of the day rather than the afternoon and evening hours - they do not need to eat in the steady "3 meals" like older children or adults do but can take in most of what they need in the morning which often leaves parents feeling like they ought to eat a similar amount in the afternoon. So please know that your LO is not much different to other toddlers, perhaps this will help.
Looking at your routine, I could suggest some things to try and see what you think.
- taking into account she eats well at breakfast you can offer different things at this time, if you like the balanced meals you prepare for lunch or dinner you can save a portion of this for the following morning and offer it at breakfast time. It sounds odd I know but I was given this advice when my DS ate almost no protein, I took the chance and offered an egg at breakfast instead of his usual muesli and he just ate it - I was very surprised I had expected him to refuse and scream his head off. I always felt much happier with the rest of the day knowing he had a full portion of protein at breakfast, it took the pressure off. He had also (similar to your LO) been refusing egg at lunch and dinner although I knew he liked it in the past. The thing was, by lunch and dinner he wasn't hungry enough to want it but at breakfast he had a great appetite.
- The morning snack seems to come quite early and seems quite big IMO. A usual snack time is around 11 ish which is getting very close to her lunch time so, you could leave the snack early and reduce the amount or switch what you offer, or you could let her wait until 11am (ie skip the 9.30 snack) and do a "split lunch" which many people find works around the nap. Basically you offer some of the lunch time food groups at 11 and the others after nap at 2pm. Have a think about how changing the timing of this snack/lunch might help.
- The morning snack, if you decide to continue offering early at 9.30am, you can switch for something from one of the food groups she is skipping at lunch/dinner - veg or protein. Whilst steam carrots or green beans might not seem like "snack food" to you, it is perfectly acceptable to offer these or other veggies, or half an egg or some cold meat or fish for snack. In terms of what you offer try to think about the portions of various food groups across the day. Each meal doesn't need to be "balanced" but across the day her intake should end up balanced. ATM it might be heavy on carbs and fruit but light on veg and protein.
- When it comes to the afternoon and evening, if you know she has already eaten a portion of protein, a couple of portions of veg and a portion of fruit you will likely feel less anxious about what she eats for dinner or the amount she eats.
- LOs obviously like sweet foods. Sure if you offer cakes and biscuits all day she will likely eat them. If it was me I'd probably cut right back for several days or cut out all cakes and biscuits for several days and then re-introduce one small portion per day once her other food groups has increased. As you are concerned about her food intake the way I would see it is that every bite needs to be from one of the vital food groups so that she is getting good quality food with the vitamins, fats etc that she needs to grow well.
- It is quite normal for weight to fluctuate a little. I believe (off the top of my head) that the guidance in the UK at this age is to not weigh LO more than once every 6 months, I think the reason for this is because weight fluctuation can panic parents and lead to unnecessary worry. It is within acceptable fluctuation for the weight to drop a line on the centile charts and would not be any cause for concern until LO had dropped two lines. If this is the case I would book an appointment with a doctor to get some additional help and support. Weight can drop when LOs are poorly or teething and their appetite drops, often they will still eat their fav foods (like cakes) at those times but refuse their normal healthy foods. They can quickly regain the weight when the teething pain has passed.
- a toddler portion is very very small. The size of their little hand is a rough guide. for example a quarter of a piece of fruit is a full portion (and many would eat a whole banana which is probably 4 portions in one go!) and as a guide toddlers would be recommended to have just two portions of fruit per day - that is only a half of a fruit! A portion of vegetables is just 1-2 tablespoons and just 2 servings are expected across a day. Looking at just how much she has might help you feel more comfortable about the amount she is eating and perhaps give you the confidence to stick to your balanced meals rather than offering additional cereals or biscuits due to worry.
I hope something here helps.
And hugs - it can be so hard for us, our natural instinct is to feed our children, try not to worry too much x