Does introducing a tree nut in the diet decrease allergy reaction to other tree nuts?

[Criteria16]

I will try to explain my question better.

My DS (primary school age) is allergic to quite a few tree nuts. Tests have consistently shown now that he is not allergic to only a couple of them, so the doctors advised to try and introduce them in his diet (under supervision, not at home). A nurse mentioned to me how good the plan was as by getting used to these nuts the body learns how to cope with these type of proteins and it might be that in the future his other allergies will disappear or reduce because of that.
I am trying to find some scientific evidence of that. Does anyone know if this is true?

Tree nut allergies are usually for life, as advised by our allergy clinic. Like you I’ve got an allergic child, he’s allergic to cashew and pistachio and carries an EpiPen. We’ve introduced the other nuts and feed them regularly otherwise he could also become allergic to the ones he can currently eat, this is what the process of feeding the other nuts is trying to prevent. While is does happen very occasionally (we live in hope too) the chances he will become less allergic to the ones he is allergic to are tiny, less than 10% so gently you need to come to terms with that so you can help your child manage it.

There are theories out there that this is the case, yes.
So some papers reported that when doing oral immunotherapy for one tree nut, some children were found to have outgrown another tree nut.

This paper highlights this with walnut helping hazelnut outgrowth:

www.sciencedirect.com/science/article/abs/pii/S235246421930029X#:~:text=Interpretation,of%20the%20allergen%20maintains%20desensitisation.

Cashew and pistachio are "sister nuts", so if you tolerate the one, you can generally tolerate the other.

Same for walnut and pecan.

@Criteria16 Just tagging you, as I appreciate you asked last week

Thank you all for your input, so helpful.
I investigated a bit more and learned about cross reactivity, which is an eye opener.
While we will still manage our DS' allergies and help him navigate life with them (nothing new, he's been diagnosed very young and we have annual reviews and a lot of support), I now have new hope.
The two nits he's now been confirmed not to be allergic have a similar protein structure to another two, so we have a reasonable chance to be able to reduce the list of allergen in his diet. There is a third type of nits tests are showing low results so I will discuss the possibility of a food challenge for that one as well with the consultant.

Thank you all!

Also cashew and pistachio often have cross reactivity with pink peppercorn. Not one I expected!

DS also had a slight reaction to peanuts in the initial skin test but now is fine with them.