The second daughter of Catherine of Aragon survives

What if the daughter of Catherine of Aragon in 1518 was able to survive, lets name her Isabella - I really see that daughter being married to the brother of Anne of Cleves which is a match for Mary Tudor that she refused or displacing Catherine of Medici as the wife of the French king.
 
What about marrying her off to Philip II of Spain, rather then her older sister?

If she is married via proxy to Francis III, Duke of Brittany and have a child before his death in 1536, she would become the mother of the new French monarch.

Could marry Francis I, Duke of Lorraine.

If she marries off to Henry Grey, 1st Duke of Suffolk (The son of Thomas Grey, 2nd Marquess of Dorset and of Margaret Wotton; through his father he was a great-grandson of Elizabeth Woodville, the queen of Edward IV of England, by her first marriage to Sir John Grey of Groby.) This would change the future for the House of Grey.
 
What about marrying her off to Philip II of Spain, rather then her older sister?

If she is married via proxy to Francis III, Duke of Brittany and have a child before his death in 1536, she would become the mother of the new French monarch.

Could marry Francis I, Duke of Lorraine.

If she marries off to Henry Grey, 1st Duke of Suffolk (The son of Thomas Grey, 2nd Marquess of Dorset and of Margaret Wotton; through his father he was a great-grandson of Elizabeth Woodville, the queen of Edward IV of England, by her first marriage to Sir John Grey of Groby.) This would change the future for the House of Grey.

The thing with Mary is that she was planned to betrothed to Protestant Princes like that of Cleves and she did not consent, it is likely that Isabella would be married to a Protestant German Prince on her teens in place of Mary, if she marries Francis III or Henry II she needs to abdicate her claims to the English crown.
 
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