Paranoid - Child Abuse

I have a 3 and 1 year old. My eldest is a girl.

These last few week I’ve had some red flags concerning my girl. She has had 2 months of UTI and now thrush infections… I thought it was related to her hygiene with toilet wiping as we’ve only just potty trained 6 months ago. In the evening, I always go upstairs with my 1 year old, for approx 1 hour, putting him to bed… whilst my partner (the Dad) looks after and gets my girl ready to go up for the night downstairs. This involves pjs milk and story time. Over the last few weeks, my girl has shown some odd behaviour. Asking her Dad to “wipe” her, stripping off, fondling her private bits and showing really intimate areas - going up to my partner doing so. I’ve had a few conversations with her about keeping her private parts private. She’ll demand my partner put cream on her. These are only what I’ve spotted over the last few weeks… a couple of times I manage to put my youngest to bed early - I normally stay upstairs and wait for my partner to bring my girl up to bed, but because of my concerns I came back down - on both occasions she didn’t have any clothes on and was on top of him and he started to go red when he realised I’d come downstairs. He does nothing to discourage her and I’m wondering if he’s done something inappropriate given her behaviour.

It’s difficult to get anything out of a 3 year old. She doesn’t know what’s right or wrong. I’ve tried to talk about nobody goes near her private parts, always keep your pants on etc. I’ve tried asking her in a way if anything has happened. That one time she said about Daddy wiping her and unfortunately my partner overheard, he walked in the room and stepped in to her talking any more. It’s really the weird shifty ness and my internal warning signs that are blaring a big red flag - something is wrong.

I’ve looked up what to do…. But I don’t actually have any hard evidence, other than my “paranoia”. I wouldn’t stand a chance in proving anything legally and we would be in an even worse position where he might get unsupervised access for days if we ended up separating. I’ve been with my partner for 11 years - me having this concern is very real, very surreal right now.

What do I do?

Edit - thank you for the comments, I’m trying to hide my suspicions… but I think he suspects that I know something as I’ve asked some rhetorical questions after certain things that have happened. He has also stopped engaging with any kind of contact with me, since I’ve started suspecting . I have considered a hidden camera. I will first leave my phone on audio record to see if there is anything suspicious then go the GP/police 😔.