Princess Charlotte proved that she's always there for her younger brother as she kept a sweet eye on Prince Louis as he attended his first Easter Sunday service.The seven year old looked adorable as she walked from Windsor Castle to St George's Chapel on Sunday morning alongside her parents Prince William and Kate Middleton and brothers Prince George, 9 and Prince Louis, 4. The Easter Sunday service was held at the 15th-century chapel in Berkshire and was the first time the youngest child of the Prince and Princess of Wales was in attendance, while Charlotte made her debut last year.