Do you think my cousin was correct in spilling the beans to his dad?

I spent 3 weeks in Europe with mysome of my closest cousins and one cousins kids on a vacation trip. During the trip from time to time (not always though) I texted my sister and tell her about how I was doing. The cousins I went to this trip with are very delicate people, they get upset with stupid things and things that are really irrelevant. One day as i was texting my sister and she asked how I was doing and she even asked me if there had been any diagreemnts among my cousins or if there had been a cousin who had to upset about anythinng I told her yes. While I was texting my sister the kid of one of the cousisn I was traveling with was reading what I was texting to my sister. I had not even noticed my cousin wa reading that behind my back cause I was walking forward whilke texting on the street. but some way my cousin kid was behind me reading the conversation and he event too a screen shot of the conversation. What this couisin did was totally incorrect, snooping on someones private conversation and even worse behind my back and taking a screen shot of what I wrote to my sister Not onky that but this cousin was a snitch and went and told his dad that my sister and me were speaking about him. The father read my conversation to my sister about him and he got pretty pretty upset at me for telling things about him and his issues to my sister. Of couse I know what waswrong from my part but my cousin kid did worse he went behind my back tooka screen shot (proof) photo and gave it to his dad and for atht my cousin stopped talking to me and up to this date he continue to be angry at me so during 5 days of our Europe trip he did not even say a word to me, silence between him and myself and im a bit sad due to this cousin and I were very close and from this incident he now I assume no longer trust me. What I spilled to my sister was only to her she did not share it wuth anyone else anyway, it was onky to her periodl.

Do you think my cousin was correct in spilling the beans to his dad?
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