Marks & Spencer used its to tweet out pictures of babies alongside a number of "royal etiquette guide" rules, including "one may greet a lady with a light kiss on the cheek, only if one has been formally introduced".
Sometimes easier said than done. Rule number two in our Royal Etiquette Guide
— M&S (@marksandspencer)
Supermarket giant Tesco, which , is collecting advice for life with a newborn through its @TescoBabyClub Twitter account and will publish the best tweets in a "beautiful baby book", which it claims it will send to the royal couple.
Meanwhile, babycare specialists Mothercare and Kiddicare have gone head-to-head with similar royal baby takeovers of their Facebook pages (see gallery).
Both brands have changed their Facebook homepage background images to include a baby wearing a crown, alongside a message congratulating Kate and William.
Seraphine, the upmarket maternity clothing brand, continued its outdoor bus campaign.
From today, the ads created by JWT London, now read: "Congratulations M’um", in a play on the regal Ma’am salutation.
Babycare product manufacturers are also getting in on the action with Johnson & Johnson publishing a "for all royal babies" post on its Facebook page, while Unilever is .
However, brands jumping on the back of the royal baby news has not been received well from all quarters, as evidenced by messages left on the Johnson & Johnson post.
Facebook user Alison Johnson said "ooh boy, look at all the advertisers racing to jump on the bandwagon :-(", while Anna Williams Hughes complained, "didn’t take Johnsons [sic] long to cash in then".