Pippa Middleton
Kate and Pippa were born just 20 months apart and have been best friends as well as sisters their whole lives. With the same passions and interests, taste in clothes, and shared friends, they were the perfect roommates when they lived in London together, while Pippa was on hand to help Kate plan her wedding and gets on very well with the royal family. The sisters still holiday together, and Pippa is a frequent visitor to Anmer Hall.
Alice Avenel
Proving that the friendships formed in teenage years can be the strongest, Alice is yet another former Marlborough girl and is connected to all those closest to Kate. Not only was she friends with the duchess at school — they were on the tennis team together — but she was also a teenage friend of Prince William and then went on to Edinburgh University with Pippa Middleton. In recent years, William and Kate went to Alice's wedding, and they are still close now. Alice's daughter Rose is just a year older than Prince George.