That’s what sisters are for, right?

Kate Middleton, 35, is helping her younger sister, Pippa Middleton, 33, plan her upcoming wedding to her fiancé, James Matthews — and if it turns out anything like her previous nuptials on April 29, 2011, to Prince William, it’s going to be one amazing event!

“Pippa isn’t having an over-the-top wedding. She wants her big day to focus on family,” an insider exclusively tells Closer Weekly in a new interview.

MORE: Pippa Middleton Gushes About James Matthews — See What She Revealed!

Her niece and nephew will have starring roles in the ceremony, too! Kensington Palace recently announced that George, 3, will join the bridal party as a page boy while his younger sister, Charlotte, 23 months, will be a bridesmaid!

Interestingly, Charlotte has been entrusted with a more grown-up role opposed to the flower girl everyone thought she’d be. So exciting!

Click through the gallery below to see the most iconic royal weddings ever!