The rise and rise of the 'mummy bloggers'
There is an immovable force in the blogosphere.
They come in their thousands, and command dedicated followings who trust in their every word.
They are the so-called mummy bloggers.
Real mothers, blogging about the minutiae of family life to offer a no-holds-barred account of life with children.
For the mums, they provide a discussion and support network, but for advertisers they are the holy grail: popular, trusted - and worth paying for.
Despicable Me is a new family film from Universal Pictures.
For the first time, the company's marketing campaign has added social media to the traditional routes of advertising the film. It specifically targeted the likes of Facebook, Twitter, but also prominent parent bloggers in the US.
End Quote Patrick Ruddell A 'daddy' blogger
They don't pay you to bash their company and say something negative about their product”
Among them was Jennifer Donovan, a stay-at-home mum from Connecticut who has been blogging for six years.
She was flown to Los Angeles, put up in a luxury Four Seasons hotel and invited to rub shoulders with Hollywood stars like Steve Carrell, Miranda Cosgrove, Julie Andrews and the film producers.
Perhaps unsurprisingly, she then went on to blog about the film - very positively.
"I will say, after I accepted the invitation, had I not liked the movie I think it would have been a little bit more difficult to do such an extensive coverage," she told BBC World Service's Digital Planet programme.
"I would probably have opted to do a little bit less."
But for the filmmakers, the expense of treating Ms Donovan paid off, and the company's head of digital, online and mobile marketing Doug Neil is transparent about his motives.
"We believe that the parents can be big influencers for us, and helping to sell the film and get their interest in promoting the film to their audience, as a stamp of approval for being a good wholesome safe film for families.
"Critics are still important but for many films they have a lesser role, as the social media aspects of movie-goer take over. We are seeing that the blogging community has lots of influence over what films they recommend and they like."From moms to mums
As with other online trends, what begins in the US soon makes its way to the UK.
Linda Jones has been writing parenting blogs since 2005, starting with her site - gotyourhandsfull.com - focusing on bringing up twins, triplets or more.
She now blogs at havealovelytime.com about trips and holidays with children, and is often - along with her family - invited by holiday firms to stay at resorts and take part in activities.
"I have been invited to Florida, and I've been to the Bahamas as well," she said, but added that free trips did not mean positive blogs if they were not deserved.
"When I'm blogging, it's clearly stated that it was a complimentary or PR-hosted trip.
"You do still highlight stuff that's negative, in a constructive way. When I went to Eurocamp a few weeks back, I came back and told them that had we paid for that accommodation I would have been very disappointed - and we included that in our review."
It is a degree of transparency which is critical to retaining readers' trust, she argues.
"The mums are seen as real people."'Sent back spud gun'
In the US, concerns over the morality and legitimacy of mummy blogs endorsing products or services has reached such a level that the Federal Trade Commission (FTC), an American consumers group, has recently addressed the situation by revising their advertising rules.
They now require bloggers to disclose and clearly label their connection to advertisers.
Patrick Ruddell, one of a growing number of daddy bloggers, says the lure of making money could be used to encourage positive blogs.
"Mommies make money, parents make money.
"They sit at home and they blog and there is definitely a good income stream you can make just from blogging. So, when money is involved there is definitely going to be some type of influence.
"They don't pay you to bash their company and say something negative about their product."
- Digital Planet is the weekly technology programme broadcast from the BBC World Service
- It is broadcast on Tuesday at 1232GMT and repeated at 1632GMT, 2032GMT and on Wednesday at 0032GMT
Back in the UK, while there are no formal guidelines or obligations for mummy bloggers to publicly disclose freebies and trips, a large number are committed to doing so.
Susanna Scott, an American who moved to the UK, founded British Mummy Bloggers, a collective of mummy - and daddy - bloggers from around the country. The group has grown to well over a thousand members, and is quickly growing.
Their philosophy is one of absolute transparency, she says.
"I tried out a vacuum cleaner. I loved it, and I wrote about it - but I do write and say that this is a sponsored post."
On top of her own blog, she recently launched British Mummy Bloggers Do It With Integrity - a campaign designed to promote transparency and full disclosures by bloggers.
"It's very important. If a blogger is working with a brand, you need to tell people. I think people have a right to know.
"It's stemming from the FTC guidelines in the US. We're in a unique position here because we're behind the US - we can learn from their mistakes."
She said that in the past she has refused to back a product, despite offers from companies.
"I've sent things back before that I didn't think were appropriate. I sent back a spud gun once. I said 'sorry, I can't do a review on this'."