In view of her 30.1 million followers, Victoria shared a short, black and white clip of her daughter in a swimming pool.
The mother of four had added a sparkling filter over the snap as Harper lay on her back and relaxed while taking a dip.
Victoria captioned the post: “Happy #WorldOceansDay from my favourite little water baby! #HarperSeven
“We’re so lucky to have our beautiful oceans, it’s so important to care for them today and every day,” she told her fans.
Victoria’s followers rushed to comment on the post, applauding the star for her efforts to raise awareness for the cause.