I might not know much about Pippa Middleton's daily schedule, but that won't stop me from making an educated guess. Or rather, taking a wild, fantastical stab in the dark.
I reckon Pippa wakes up in her fiance James Matthews' multimillion-pound Chelsea mansion shortly after 11am, throws off £2,000 of Pratesi bed linen and is immediately brought a Buck's Fizz by a faithful retainer. She slips on her custard cream-sized engagement ring and goes to meet her personal trainer, who is rumoured to be the person who taught Beyoncé how to dance.
She goes for a blow-dry - in my imagination, Pippa has not washed her own hair since 2005 - and has a fabulous lunch with glamorous insiders who tell her Made in Chelsea plotlines a year in advance.
She takes a suite at the Ritz for an afternoon nap, and then gets up and buys handbags until it's time for dinner with James, who is so bored of the Chiltern Firehouse that he's wondering if she could bear a trip to Sexy Fish, and has bought her a wheelbarrow filled with rubies in order to make up for the inconvenience.
We know much more about big sister Kate's routine, because we constantly see her stuck in an endless schedule of tours and photo calls. She spends most of her time at schools and hospitals, wearing a series of sensible Reiss frocks on rotation, occasionally going wild and splurging on a nice new coat. As the mother to the heir to the throne and his little sister, she's been tasked with setting an example to the whole nation.
Sometimes I imagine her WhatsApp conversations with Pippa, and I feel desperately sad.
"Come out tonight? We're doing DSTRKT and then this chap, Pongo something, is having an after-party on his new yacht - apparently it's twice as big as his last one!"
"I can't - I've got to puree all this broccoli, then first thing tomorrow we're off to cut the ribbon at the new Centre For Incurable and Horrifying Diseases. I really should spend tonight familiarising myself with all the diseases."
It's a sad song of sibling sorrow, but one that big sisters like Kate - and me - are painfully familiar with. We strive to do everything that our parents hope for, only to realise that despite doing our best to blaze a trail, our younger siblings have had much more fun by not having to follow the rules.
I used to think about it a lot when people compared my five younger sisters and me to the Bennett sisters - Jane is the eldest and most sensible, and while the pressure is on to get her married off, the others seem to have a much more exciting time.
My parents certainly put pressure on me to set a good example, both short-term and long-term, and kept having these conversations with me about "WHEN you go to university... WHEN you graduate... WHEN you get a job... WHEN you marry...". My sisters, meanwhile, were considered a success simply for being alive and not having set anything on fire.
When I made my First Holy Communion, I wore a white dress and a veil, and had a fairly solemn party thrown in my honour, where every member of my extended family presented me with a religious gift. When it was the turn of my youngest sisters, they wore cool white trouser suits like mini Bianca Jaggers, and were given Bratz dolls. It took me months to convince my parents to let me choose theatre studies as an A-level option.
A year later, my sister Beth decided she was going to a distant college to study something like balloon modelling, and was praised for picking a subject she was passionate about.
I've had this conversation with every big sister I know. We weren't allowed to think about getting our ears pierced until we were 16; then our little sisters sneaked off to get their belly buttons done, and were met with nothing more than a roll of the eyes and an instruction not to let them go septic.
It sets the tone for adulthood. Some rumour-mongers may claim that Kate was encouraged to study art history at St Andrews University in order to "bag" her prince, but one can assume that as soon as her future became a matter of national news, no one would have minded whether Pippa got a first in English literature (which she studied at Edinburgh) or a third in yacht operations.
As a freelance journalist, I might not have a "proper job" but I've certainly attempted to make sensible career moves in order to make my parents proud. My much more experimental younger sisters are all very successful but I'm not sure they've ever felt pressured to be anything beyond "employed".
Similarly, while Kate has taken on a limited number of sedate, grown-up roles - accessories buyer at Jigsaw, consort to Prince William, mother of heir to the throne - Pippa has dabbled in pretty much everything, from party planning to magazine columnist and brand ambassador work. What's more fun - attending endless dreary banquets where you can't get drunk without causing a diplomatic incident, or putting together a jolly few hundred words for Waitrose magazine about having your mates over on a Friday night for spring rolls?
However much Pippa may have been enjoying herself, Mummy Middleton has alluded to the difficulty of being a parent with a child in the public eye, saying "I don't want the attention [on Kate] to detract from [the others]... I have three children - not just Catherine."
Perhaps this is the hardest pill of all for older sisters to swallow. We put ourselves under so much pressure to be perfect in order to achieve parental praise - only for our parents to lavish even more attention and affection on our freewheeling younger siblings, so they don't feel "left out".