I have OCD and don't have a single cleaning compulsion! None... I have no germ thoughts so it's not always that.
Obsessive thoughts are horrendous, it took me a while to understand that our brains can lie to us and not everything that we think is true is actually true. And I was 22 when I was at my worst. I don't do many rituals at all (sometimes knock on my door when I lock it and occasionally mess overwhelms me but that's it).
Mine were mostly thinking that I had to leave my partner and that we were going to get a divorce (were not even married) and that he'd die and I'd lose him. I had them at work sometimes and would cry in the loos and have panic attacks - no one noticed a thing.
Watch the TV show Pure - she has a form of OCD called Pure O... no rituals etc but she has exactly the inappropriate sexual thoughts your daughter is having. I've had them too.
Here are some mind tricks that really helped me.
- The Gremlin-
It's difficult not to think that the thoughts are what you want or true because they're YOU thinking them. So, when one pops in, take the thought and see it as being said by the 'intrusive thought monster' who is sat in the corner of the room. When one pops up, imagine throwing it back at the gremlin and telling it to keep its thoughts to itself.
If that's too scary maybe moderate it to her age.
- Positive refraction
When a bad thought comes to mind, instantly think of a good thought. So... kill mum now, think 'HUG mum now' straight after.
It sounds silly, but our minds operate by moving through familiar patterns. The more often we have a thought the easier it is for our mind to wander down that thought path. By counteracting the thought with a good one the mind eventually finds it easier to think the good thought path rather than the bad one.
They helped me and might be a good start while you're waiting for help.