This post is two-fold.
First I'd like to explore the underlying causes for the relationship between the Queens going sour.
And secondly I'd like to look at the consequences if this continues.
Okay, I understand Queen Letizia and Sofia once had a good relationship, or at the very least a working relationship.
When did the first evidence of the a deterioration of their relationship show itself to the public? - Because that may hint to what may have caused it.
I've seen Christina being suggested as the cause. I'm not sure I buy that one. Queen Sofia, and her extended family, if any, understand that a Monarch sometimes have distance himself from certain people, even family members. Queen Sofia is experienced enough to know the complicated issues in regards to the public, let alone the royal family's image and the political concerns. - And that of course applies to the Monarch's wife.
And in anyway it may only be for a few years then Christina may queitly be left back into the fold.
So while Christina may have been the trigger, I doubt that is the thing that began to sour their relationship to such an extent. IMO something happened prior to that.
Queen Sofia's extended family (of fellow royals mind you!) clearly have serious issues with Queen Letizia! It's not just about an disagreement about lacking support of a family member, (Christina) or a disagreement about what role Leonor and Sofia should have in public. This is personal!! They are genuinely hopping mad at Queen Letizia!
Queen Letizia haven't exactly helped the situation by snubbing her mother-in-law, a Queen no less, in public. To mention one episode described here in this thread.
On the other hand there is a reason why she would do something as foolish as that. What? Tit for tat? Payback for previous humiliations?
Or are we talking about Queen Letizia being too sensitive and even vindictive? I.e. she has been waiting until she became Queen, so that she could give some serious payback? - If so, we have a serious psychological issue on our hands!
Or is it bitterness that has been build up over the years, due to her being subjected to humiliations? Snubs? Wounding remarks? And now that bitterness can no longer be contained?
Queen Letizia has in my opinion made a number of serious mistakes, both PR-wise, but also on a personal level. If it is true that she has denied Leonor and Sofia access to their own grandparents, then it's bad! I can hardly imagine anything that would hurt and infuriate otherwise loving grandparents much more!
If that is the case, then King Felipe is a wimp IMO! He should have put his foot down and said of course his parents can be with his children without being supervised.
Let me be clear, King Felipe has not impressed me in this. He has allowed this to go on without putting a decisive end to it. He is basically the only one who can put an end to it. He is now supposed to be head of the family.
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And from that we go to the consequences if this persists.
Because if this feud is allowed to persists and King Felipe cannot control it and stop it with the necessary means, like therapy. He will be forced to take sides and soon... - In such a stand-off he will IMO almost certainly side with his wife. He is after all married to her and I assume he loves her. She is the mother of his children, the mother of the heir, who is facing enough difficulties as it is in the coming years. A divorce is hardly an option. At worst he can unofficially separate her, but not divorce her. - And what if he genuinely feels that Queen Letizia is the one who has been wronged here?
And to be very cynical: His parents will become more and more frail in the coming years, while his wife remains - in fine form...
However, judged from the critique and descriptions I have read about Queen Letizia here in the past few days, it's my impression that she is a very strong-willed woman.
I think, I'm actually convinced, that if King Felipe sides against her, she will divorce him. - At best she will separate him. Because to her that would be a betrayal.
I don't envy King Felipe, because he has some unpleasant decisions to make and soon!
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Another matter I think I will mention is more psychological.
It has been mentioned again and again that Queen Letizia is keeping her daughters very close whenever they are in public. It's to me almost like the girls are some sort of psychological anchor, a mental life-jacket if you will. As long as she has the girls under control, she has someone who is guaranteed to be on her side. Someone who will remain her allies.
It's a psychological mechanism you sometimes see with people who under severe stress.
Okay, it could be because she's a control-freak, but I honestly don't think so. To me this is more a symptom of someone who mistrusts most of those around her - for whatever reason.
In such a situation you tend to protect (perhaps over-protect) what is most precious to you.
- And thus ends this psychological amateur-analyses from me.
Oh Lord....!!
You have put this whole thing into a context. On its own the 'dust-up' seems way over the top, but seen as a generational issue, it makes sense. Thank you. Great perspective supplied. 
)and being as spontaneous and charming as you often see the Royal children of Britain, Sweden, Belgium and Denmark. 
