hmm i think Eric is right..
the princesses was very close to each other, and they did helped each other all the time. sure, Irene wasnt so close with VHM, but they was sisters and they loved each other. Irene was just to quite to find out something which was the reason why she did burned her letters. We only knew about the illness of her sons..the happy Marrige and not more..we dont know about her hobbys..what did she liked and disliked..and we know that she has a good heart, and let build a children-hospital..But if she was so closed like alix or if she has such a big humor like Ella we dont know it..
its very hard to say anything about her...I wonder what she did wrote in her letters..did she wrote Letters to henry, while he was on the Sea ? what has she done all the time at home..did she teached her sons self (like her sister VHM did) ?