spiteful DD

[MrsB1]

I have 2 daughters aged 14 and 10. They are like chalk and cheese and often squabble. I accept that this happens in families, but the younger one is becoming more and more spiteful and hateful towards the older one, and it breaks my heart.
She treats her like a leper, doesn't like her touching her things, says it makes them dirty. Eldest is suffering with her skin and hair at the moment thanks to puberty, and being told things like " you cant borrow my pen, I don't want it getting greasy" are not helping one bit.
Last night lDD2's hula hoop rolled across the room and bumped into DD1. Because it had touched her sister she went and got some anti bac wipes and cleaned it.
I hit the roof, told her it was unneccessary and unacceptable behaviour. Eldect handle it really well, with sarcasm but as soon as we were alone poor thing broke down in tears.
Has anyone else exepienced similar, why is she doing it, and how do I stop it. I realise I cant make them be best friends but this is beyond stressfull !!!!

I think you have to stop this being an issue between sisters - your DD2 behaviour sounds appalling and I would be focusing on how she is behaving like this to another member of her family.

I would be removing something of value from DD2 (or DD1 for that matter) every time she does something that implies another person in your house is dirty / greasy / unclean, and she has to have been civil to that person for 24 hours to get it back.

sit down with DD2 and bluntly say that "in this family, we do not treat other people like that" How would she feel if you froze when she went to give you a hug? She has to realise that her behaviour is not acceptable.

Stop being stressed and start being angry and imposing sanctions for this behaviour.

I agree with the above, your dd2 is behaving unacceptably and sanctions must be applied. Sit down and devise a plan about what you do for each instance, what she loses if several incidents happen over a week etc. Also, you need to take dd2 aside and give her a full explanation of how awful and hurtful her comments are and explain the sanctions that will happen going forward if she doesn't change. In general, is dd2 feeling that she doesn't have enough space/time? You may want to ask her if there is any underlying problem, while making clear the comments etc must stop.

DD2 has always been a bit of a Diva, loves to be centre of attention, seriously does seem to believe that she is the most important member of the household. We can usually manage her megalomania but this aversion to her sister at the moment is REALLY hard. I have even considered that it may be some form of autism or ADD.
Thanks both, we have a bit of time together after school before DD1 gets home, I'm going to try and have a chat with her, let her know how much it upsets ME, let alone her sister and lay down some new boundaries.
Wish me luck

Good luck op! You're doing dd2 a favour too, this will affect her relationship with her sister if unfixed.