dd is 2.4 and ds 6.5m. dd has always been pretty good with him from the start. apart from one thing...waking him on purpose from his naps. we live in a bungalow so all on the same floor. dd goes off and does something on her on no problem for the 4/5 mins it takes me to put him down then i come thru shut door and we go and play etc. she then progressively becomes louder and louder, starts to shriek and scream and run around and if i don't catch her in time she hammers the bedroom door and screams/yells etc and ends up waking ds up. the more i say don't do it the louder she gets. can't put her on the naughty spot as she will have a loud tantrum or if i threaten taking away something etc she will run to his door screaming crying etc. its like a game to her. i often take her into garden but then she starts screaming and crying and trying to run in. its such a shame as if left he will nap for a good hour which means we get some alone time but she just thinks its funny. what can i do???