She's the woman who is exactly like you, and yet she has her own quirks that aren't quite like yours. When shopping for her, you don't have to worry about whether she'll like it or not because you've known her all your life. But out of the thousands of things she wants (just as you do) what do you buy her?
Whether she's a book worm or a fashion devotee, we've pulled together 10 beautiful items that we hope will give her that wide, teeth-revealing smile all gift receivers at Christmas should get.
Aromatherapy Associates Ultimate Bath Jewels
Aromatherapy Associates' award-winning bath oils have been packaged into one handy box for the first time. Like a shower menu, she can choose the pick-me-up oil she needs every morning, from de-stressing to strengthening for the day ahead.
Alighieri Broken Wings necklace
Give the gift of angel wings this Christmas with this 22kt gold plated bronze piece. The perfect keepsake.
Johnstons personalised cashmere scarf
Burberry's monogrammed blanket scarves are the accessory of the season. She'll be right on trend with Johnston's cashmere alternative, that costs at a fraction of the price.
Matilda mini poster
Instill memories of getting lost in a novel with this illustration print of the ultimate book worm Matilda, by Quentin Blake.
Vivetta Hands Collar
For the quirky and stylish dresser, this accessory will instantly refresh an outfit but never date.
'Eat cake for breakfast' journal by Kate Spade
All the wishes she never completed, all the recipes she never tried, all the to-do's she never checked off - this clothbound Kate Spade journal is the perfect place for it all.
Hershesons blow-dry voucher
Gift that fresh post-blow dry feeling on a special day of her choice. (If she can't get to a Hershesons salon in London, why not find out if your local salon offers similar vouchers?)
Zara faux leather skirt
End her hunt for the perfect leather skirt with Zara's A-line piece. It's prim enough for work and light enough to blow around in the breeze on the weekend.
Swarovski stardust bracelet
Scratch off world map
Pair with a collection of travel books of the destinations she's yet to visit; the best gift for a sis consumed by wanderlust.