I came on here as we have just discovered some inappropriate stuff on DD's, also 13 phone, and I saw your post OP and its similar apart from the boyfriend part.
I do check it but hadn't done so in few months as felt I needed to give her some space, but I now regret not checking more.
I have found porn and pictures and some of the stuff she is saying and sending is truly shocking! She is also talking to so many different people, she quite clearly doesn't know in RL.
She also seems to of alienated her friends and we are concerned it may be the start of grooming.
She has lost her phone since we found out on Saturday and she hasn't even asked for it back because she knows what we have seen.
At the moment she won't be getting it back at all, and when i do decide she can have it there will be restrictions on what apps she can download and I have put an app on to track how long she is spending on certain things and block...how well this will work I do not know, and these kids always seem to have a way around it.
I am not sure what to do going forward as I can't withhold it forever and she has already fallen out with all her friends, and will probably spend the summer alone, on top of already being isolated in lock down. She was always a very sociable person, always had friends etc, up until a few months ago.
Now she won't even barely leave her bedroom let alone the house.
I am worried if I stop her using all the apps all her friends use, she will become so isolated, it could be a disaster! But she also can't be trusted to listen.I have had to speak to her before about her 'oversharing', but it clearly hasn't made any difference I have allowed her to have certain social media apps with the understanding I know her usernames/passwords etc, but she has just created several other accounts that I knew nothing about.
I haven't even spoken to her yet (her dad spoke to her briefly on Saturday after having a brief look at her phone, but I have found more since) and she just clammed up.
So I am really not sure how to approach this, I don't want to get angry with her but she also needs to see how inappropriate her behaviour has been and the blatant rule breaking with multiple social media accounts
Its a bloody minefield out there and I don't know what to do!