If so, when did they start?

I only keep a few toys in the girls rooms. They go in their sometimes but DD2 is little enough that I start to get nervous when she's gone, despite her room being child proofed. DD1 is getting at the age where it's totally appropriate but she's pretty attached to me, plus wherever she goes, baby sister follows so I don't mind having them in the common living room/kitchen area for the most part.