As part of the deal, Duplo will have a table exhibit and the brand logo will appear within the event brochure.
The event takes place at The Brewery in London on Saturday June 25th. Cybermummy expects 400 attendees and boasts a collection of the most prominent speakers from the mummy bloggers scene.
Like other toy firms, Lego has embraced the parent blogger community as part of Duplo’s social media campaign, launched in August 2010.
To date, Duplo has had digital display advertising selection of the key websites in the scene and is planning more for the autumn, while securing product reviews and offering unique ‘birthday party packs’ to bloggers.
Duplo brand manager Claire Dorrington said that the mummy blogger movement "is now a powerful influence within the media world."
She added: "The online environment is where mums and dads meet, chat and form opinions about all sorts of topics.
"It provides a great arena for us to engage them in the Duplo brand, sharing information on the benefits of the toys.”