Family outings in case of rain
I'm looking for ideas for family outings for this weekend that would be out of the rain. Children are ages 4, 5, 8, 10. We planned to go into Brussels (we are in Genval), but with the weather prediction I'd like a plan B. Preferably something where the kids can move around and that is either free or not too expensive, somewhere near Rixensart/Waterloo/Brussels or nearish.
Any ideas? I have looked at the petit moutarde website but not finding anything convincing yet.