What is the definitive guide to kid-friendly activities in Stockholm according to Mommy Poppins?

I'm sorry, but the available content doesn't directly address kid-friendly activities in Stockholm according to Mommy Poppins. However, Mommy Poppins is known for providing enriching experiences for families, including cool, artsy activities, urban nature exploration, and even grown-up events that are good for kids.

Would you like to know about any specific type of activities or events in general that Mommy Poppins recommends? Or perhaps you're interested in their recently announced book, "The Young Traveler's Journal & Activity Book," which is filled with creative activities for different adventures?