Hm, sadly this is an aspect of his life that’s missing or at least very light in many of his biographies (his relationships with his siblings/family, that is)! Perhaps there’s just not that much information in regards to it; or perhaps it’s not one historians/biographers/authors don’t find interesting…personally I find historic family dynamics fascinating, so I wish more would!

Not sure where the Arthur thing comes from, but it’s a common vein in fiction…maybe it’s that Henry threw his jacket off during dancing at his wedding? But I kind of doubt that was Henry trying to ~overshadow~ him, more likely him just like….being himself, dfskdjafks?

There’s a story of Henry throwing a tantrum when he found out Margaret Tudor would outrank him mentioned in Game of Queens by Gristwood, but no source mentioned. Later in their lives he wrote to her that “Divorce is Bad” basically ssksksk at her own marital woes…idk what her reaction was to that; I assume smth along the lines of “don’t throw stones at glass houses”. 

It’s repeated that Mary was his favorite– perhaps he felt protective of her as a younger sibling; but his affection wasn’t greater than his ambition as he married her off to the much-older Louis XII when she was 18 years old. He forgave her eventually after marrying Charles Brandon without royal permission; found himself unable to do the same when she was against him re: the Great Matter and her animosity towards Anne Boleyn caused a great rift in their relationship, from what I can gather. Her last words to him, before her death in 1533, certainly suggest this:

Has been very sick “and ele ates” (ill at ease). Has been fain to send for Master Peter the physician, but is rather worse than better. Trusts shortly to come to London with her husband. Is sure, if she tarries here, that she will never “asperre the sekenys.” Will be glad to see the King, as she has been a great while out of his sight, and hopes not to be so long again.