My cousin blocked me on Instagram?

Today I noticed my cousin stopped following me, and somehow I've stopped following her. I thought it was a technical problem so I went onto her profile and clicked follow. It said following for less than a second before it went back to just saying 'follow'. Then I noticed it said she had no posts yet, but in the section where it says how many things shes posted, it said 1387. So shes obviously blocked me. And it turns out she blocked my sister too. But I only have one reason in my head on why she might of. Yesterday, she posted a picture saying her boyfriend cheated on her. I told my mum a couple of hours after I saw it, but my mum was on the phone to my aunty (her mum) and I don't know if she said anything to her about it. Could this be why she blocked me and my sister? She posts some pretty inappropriate stuff on there, but shes never minded me and my sister seeing it, so I don't think she blocked us for that reason.