should we write a note back? she left blood clots in the bathtub!

I live with my boyfriend, our one year old daughter, his two brothers, his Dad and his older sister. His sister just moved back a month ago after being kicked out from her friends house. My bf and I have always done all the housework. We're moving out in two weeks so we've cut down a bit because we've been packing. She has been writing and taping up notes EVERYWHERE, all over the house, saying  that we need to do this and do that, and that we need to keep the bathroom spotless for the next person. We have no problem with this. She put up more notes last night saying we need to do all the towels in the house and all the laundry. We do that, shes done it once or twice. Last night we go to give our daughter a bath, and she had taken a shower before, and she left period blood all over the side of the tub and blood clots in the bathtub, which floated up during my daughters bath. We are both furious. My friend said I should write a note back about how she should clean up after her own period, and now I'm tempted to. Thoughts?