Princess Beatrice and Princess Eugenie have joined Prince William at a royal party. The Princesses of York stepped out for the Sovereign’s Garden Party at Buckingham Palace on Tuesday afternoon. Eugenie and Beatrice were joined by Peter Philips, Zara Tindall, Mike Tindall and the Duke and Duchess of Gloucester for the rainy engagement. Crowds waited in the Buckingham Palace gardens under a sea of umbrellas for the Royal Family members to arrive this afternoon. Princess Beatrice looked striking in a crimson maxi dress with pearl detailing by the British fashion brand Beulah. She paired her outf…