I don't know what to do ..

So I made plans with my boyfriend to go do something with his family on Saturday and we've had these plans for about a month but I got a call yesterday saying I get to go visit my dad who is in jail and I haven't seen him since November of 2016 .. and I told my bf and he wasn't quite understanding.. he said it would be wrong because I would be canceling on his family. I don't really know what to do .. advice ? Help ?