Liking my half siblings cousin?

Liking my half siblings cousin?

So I have 2 half brothers (we share dads) but I see there moms side of the family sometimes during Christmas at there grandmas house and they have this cousin I think is cute (I'm 17 and he is 18) , and the last time I was there I noticed that he was looking and smiling at me a few times and he playfully grabbed my bag and my stupid self didn't really do anything but look at him back and looked at him when he wasn't looking and when he grabbed my bag I just said um and took it back and my brothers mom saw he did that and reacted saying why you grab her bag and when we were gonna leave she told him she's leaving and he was smiling. Anyways I liked one of his post on Instagram but have not followed him yet because I am too nervous (he hasn't followed me yet either). I have been intrested in him for a long time now so I was wondering do y'all think I should try to talk to him also would y'all think it would be ok to do so , and how should i approach him next time i see him?

Liking my half siblings cousin?
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