DS(6) is now officially underweight

[NoCapes]

We've always had eating problems with DS since the very beginning
He was under a specialist until he was around 3 & 1/2 when his issues seemed to be under control and things were getting better so we were discharged

He's always been a tiny little thing due to his issues and other health problems but his weight was either steady or increasing, he's the smallest (in height and general size) in his class, has feet that don't grow and has always danced around the 4th percentile

Until recently - now he is losing weight and I could just cry
He can't afford to lose any weight, he is now officially underweight
He is eating the most food he's ever ate in his life and I just don't understand how he is losing weight! Maybe not particularly gaining any, that'd be fine, but losing?
Just feel like shit
What is wrong with my boy?

At 6 they are constantly on the go maybe he's burning more than he's eating. How is he in himself? Such as energy levels sleeping toileting socialising skin tone etc.

What issues with eating did you have? Just that he refused to eat or that he physically couldn't eat much due to reflux or allergies etc

His eating issues were basically that he used to make himself sick when he ate, he would just sit and heave on purpose until it came up. Then he learned that if he coughed enough that made him sick too, so he used to force himself to cough until he vomited.
He would do this every meal for on average 5 days a week, he actually did himself a lot of physical damage and now has respiratory problems as a result (asthma and recurring chest infections)

His eating now is still a battle, it can take him up to 3 hours to finish a meal (I have only allowed this a handful of times just as an experiment, I never normally let a meal last for more than an hour) and during the whole time he has to be reminded to eat; have the cutlery in his hand, put food on it, put the food in his mouth, chew, chew, chew, chew again, swallow
I think he has slight sensory issues, he massively prefers anything cold over anything hot and has a few 'safe foods' that are all cold and very bland and has times when these are literally the only foods he will eat

He has a lot of allergies but no food ones

He also has had issues with his sleep, he would cry until he was sick every single night and never slept before 2am until he was about 18 months, didn't sleep through the night until he was 4, and even now he has night terrors once or twice a week

There is nothing wrong with his energy levels (believe me!) he has the odd day where he doesn't want to get dressed and just wants to lay on the couch (don't we all!) but this is probably linked with asthma and/or having a bad nights sleep
He is pale, very very pale but always has been
Toileting totally normal

We've had a lot to contend with but I thought we were managing it all rather well now, so him actually losing weight has knocked me for six a little bit and I don't know what to do

Sorry that was really long I wanted to answer all of the questions

Anyone got any advice? Similar experiences?

It's sounds like he has massive sensory issues to me. Have you explored his sensory processing with a health professional?

Can you feed him things that are quicker to eat and require less chewing more often?

Mine luckily have no issues with food, but they both eat more if the food is easier to eat. For example rice with sausages and veg will take far longer than say sausage casserole or mushroom risotto that's already in but sized pieces and they can just shovel in!

Things like risotto, porridge, yogurt, custard, casseroles, soups, scrambeld egg

My son is very small for his age he will be 7 next week. He is now only on the 1st percentile for both height and weight and his feet are a size 8.5 which they have been since he was 3. He eats everything apart from raw tomato so no issue there and all blood tests, stool samples and MRI are normal. Consultant said at his appointment this week he is not concerned and that he will grow when he grows, can't say I'm particularly happy with that answer. To put things into perspective he was over 10lbs at birth and on the 98th percentile at birth and was average size until age 3.

Nothing's ever been picked up by health professionals and I've never mentioned anything beyond him making himself sick tbh, it all took a back seat to his actual health problems and I thought once his health was better that everything else would fall into place...it hasn't
I don't know anyone in real life with sensory issues so I'm not really sure of the scale (iyswim?) YouAreMyRain maybe I should try to get a professional involved

Art I do try to make meals as easy as I can, thing is he's not a huge fan of 'wet' food or one pot dish kind of things, he very much likes his food to be seperate entities so we're pretty limited in easy to eat foods
Any more suggestions would be massively appreciated though?

TheSun our DS's sound similar, DS was 8lb 5oz born and a chubby little thing ... until we introduced solids
It's so worrying isn't it? Not very reassuring that the GP isn't doing anything to help
I used to be told a lot that he would eat if he was hungry - they didn't know my DS! He just will not!

Op my son does eat and still doesn't grow or put on weight but the consultant that has been monitoring him for the last 2 years assures me that he has no underling conditions causing him to be small, it is just his dna. Although if your gp won't refer to the hospital you won't of had the reassurance. As a guide this is what my son has had to eat today,
Breakfast - cornflakes and a banana
Snack- apple and blueberries
Lunch- cheese and spring onion sandwich, crisps, carrot sticks and cucumber.
Snack- easter egg
Tea- slice of pizza, new potatoes and salad with salad cream to dip.

TheSun I just meant similar in size, didn't mean similar issues
I think maybe we need to head back to the GP