When DD2 has a day sleep DD1 knows she can't play in there. I tell her I am going to put J down for a sleep so if there's anything she wants to play with she needs to get it out and she can play in the lounge room or outside. She has learnt to plan better doing that so she thinks about what she wants and gets prepared. Often she will just go outside and play int he sandpit or we will do some craft in the kitchen.