I am going to Disney with son and DIL and my grandsons 2 and 4. I want them to get Park Hopper tickets.We will only be there for 3 full days. One day for MK and one Pool day and one day at MGM. I have my tickets already. On one of the days we are gong to MGM and then mom and dad are going to the California Grill for dinner.I am babysitting. I thought that night we could go to Epcot and watch the fireworks.But I can't do that if they don't have park hopper. Could I just add park hopper to my grandsons ticket , or do they all have to be the same type of tickets? If I can , can I do it at the front desk? We are staying at CR.