Do you think that she has any significance, she is a sheikia right (spelling?) does she have any relation to zelda could she be the one who taught zelda how to be sheik, like in OoT zelda transformed into sheik did impa give her the costume and such. Also are the grannie is impa in the future right? But why is she so out of shape and hide her face could there be some kind of secret??
It's actually Spelled "Sheikah", you were close though.
Her significance in Skyward Sword was definitely a needed role in the game. when you first meet her in the Sealed Grounds, she is an elderly woman in a large red hood. This is in the future however. In the Past, she is a slender, skillfull young woman who was destined to protect Zelda, the Spirit Maiden (or rather, the re-incaranation of the goddess Hylia).
Throughout the series, we have mention of a nurse-maid to Princess Zelda, named Impa. She was sort of in LOZ, AoL, and ALttP. We actually "meet" her in the OoX series, where she was traveling through different lands to find the Oracle of Ages and Seasons. Then in Ocarina of Time, -she said to be a Sheikah once again- and is one who built Kakariko Village.
She's basicly in most of the Zelda games, wether Zelda is there or not.
@JuicieJ: When people get older, their spines start to get soft and get hunched over. But it's wierd as to Impa's height as she's atleast 5"9.