Apparently, her little brother doesn't care if his older sister is one of the biggest names in Korean entertainment, because he's もっと見る bent on ignoring her. IU(アイユー) uploaded screenshots of her conversation with her little brother onto her fancafe, and most of the chat is IU(アイユー) trying to get her brother's attention によって texting "Hey" over and over again.
At one point, IU(アイユー) gives up with the string of "Hey"s and says instead, "If あなた keep ignoring me, I'm going to stop giving あなた all allowances." Only then he answered, "Why?".
After a few 'conversations', she finally concluded. "Oh, I guess あなた just don't read my texts anymore."
The conversation amused many fans, who commented, "In the end, they're just normal siblings..", "To him she's just the annoying older sister", and "She's looking out for you!"
source: allkpop