A/N: This is a hurried work, so I'm sorry if there are any bad mistakes. This idea came to me when I was buying groceries.
Elsa was lying on her stomach and drawing in her own room when Anna came in and stared at her drawing for a while until she said, "Elsa, can I ask you something?"
Anna had just reached the terrible age when her curiosity was endless. Elsa was almost tired of answering Anna's countless 'why this' and 'why that' questions, but she wanted to humor her sister nevertheless.
"What is it this time?"
Anna knelt down and took a similar position as her big sister, lying on her stomach, just opposite of Elsa.
"Have you ever kissed anybody?"
"No, I haven't," Elsa answered offhandedly and continued doing her drawing.
"Do you have anybody you would like to kiss?"
"Anna, that's none of your business!"
Actually, Elsa didn't have anybody she would like to kiss, but that's something she would never tell her little brat of a sister.
"Why do people kiss?"
"It's just a way of showing affection to the persons you love."
"Can you get germs from kissing?"
"I don't know, I guess not. Why don't you go and bother mom or dad for a change," answered Elsa. She was starting to get annoyed answering Anna's questions.
Elsa thought Anna actually did as she had told her when she started getting up from her lying position. Then she felt a moist kiss on her lips and heard the words, "Thank you, Elsa. I love you."
Elsa got up quickly. "Ptooey! Ptooey! Yuck, baby spit."
"Hey! I'm not a baby anymore," exclaimed angry Anna.
"Why did you do that for? You can't just kiss your family members."
"Why not? Mommy kisses me sometimes."
"That's a totally different thing. Parents can do that. But you can't kiss your siblings."
"Why not?"
"Because… Because… Because it's weird."
"Why?"
"Because… it just is, okay?"
"I really don't understand, but okay," replied confused Anna. Then smile came back to her face, and she said almost teasingly, "By the way, you tasted better than mommy."
"ANNA!" shouted aggravated Elsa, "Get out of my room! Now!"
To strengthen her threat, Elsa picked up a Barbie doll - ready to throw it at Anna if she didn't obey her command.
Anna just laughed when she ran out of Elsa's room.
A/N: I unconsciously borrowed 'baby spit' part from The Simpsons episode (Treehouse of Horror, season 2)