Erik could only laugh at Doreen's reaction. He appreciated her devotion but knew well enough how it feels to be lost in a sense of constant working, to feel like you're always plugged in. It actually took him about 3 years after Peter was born to learn how to separate himself from work, especially when at home or on short vacations with his family. Still, he did it, so he thought she might learn as well in time.
With his ears already following the sound of commotion, Erik accepted Doreen's idea in a flash. Armed and ready to capture their over-active children, the two hastily went down the corridor the boys were on and prompted their attention. "Stop right there!" - Erik hollered with a slightly amused tone, yet attempting to sound menacing. Peter gave no quarter. Without so much as a word, he dashed at his father with his sword raised and ready to strike. Parry. Erik stood his ground and waved the plastic decoration around as decently as he could, just enough to make it interesting but still maintain a level of safety.
Ben on the other hand tried a more indirect approach and came close to his mother from the side of the corridor, ready to pounce.