The work, the first to be produced by Banks Hoggins O'Shea/FCB since picking up the business in November last year, aims to take the brand back to its "maternal" roots while making it relevant to today's mothers.
The new initiative comes as the cereal sector struggles to overcome the damage to sales caused by changing breakfast habits.
The £1.1 billion UK cereals market has declined in volume, with children's brands being hit badly.
However, Ready Brek has been bucking the trend thanks to its new Rip Mix and Micro range, a microwaveable sachet variant that allows older children to make their own breakfast.
Mark Mylod, whose credits include The Royle Family, The Fast Show and Ali G The Movie, directed the two 30-second spots through Tomboy Films. Breaking nationally on Tuesday, they feature mothers having to face the fact that their children are growing into mini adults to underscore the fact that Ready Brek still gives them the chance to show they care.
The ads were written by Bryn Attewell and art directed by Mark Robinson.
PHD is planning and buying the media for the campaign, which is adopting a TV-led approach to relaunch the brand to its core audience of young mothers.
This is being underpinned with radio and ads in the parenting press.