My dad found me after 22 yrs?!!?

my dad found me an my sibling after 22 yrs! He said my mom moved away and hes been looking for us ever since......i met him and a BUNCH of family i nvr knew i had last week and now he wants to go over his house for the weekend with him his wife and 3 kids who are 9, 12 1nd 15. Do you think this would be a good idea, what should i expect??? Our siblings wanted to meet us and knew we existed through the baby pics and our dad telling them about us but they seem reallllllyyyyyyy shy around us....what can be done to break the ice and such????