I regularly talk to Ben about Kaia--what she's doing, who she is, etc. This will range anywhere from "See your sister dancing?" to "What a wonderful big sister you have!" to "I need to spend some time with sister now."
(on a side note, I always swore I'd call my older child by their name. I don't like the nickname "Sissy" especially, but calling the older child by their relationship to the younger seemed diminishing. So I said "not me! never!" Then Kaia starting requesting to be called "Sister". I finally gave in to her wishes. I figure if it's HER wish, then it's ok. I still refuse to say "Sissy" though.)
Back to what I was saying, I find this talking to Ben about Kaia has two main benefits. It helps Ben get to know his sister, and I can "tell" Kaia things, such as that I think she is a wonderful big sister. Telling Ben (I tell her directly too) makes it seem more special to her, like I'm bragging about her to someone else.
So this morning, as we are leaving, Kaia comes in putting on her coat. She explains that she has on a sweater and a long sleeved shirt so that she can take things off or put them on depending on if she's too hot or too cold.
I told her that was a great idea, then told Ben that he "sure is darn lucky to have such a smart sister".
"Yeah!" chimed in Kaia. "He IS darn lucky! As darn as lucky can BE!"
My god do I love age six!