I didn't like the 15 yrs later thing either. Also notice that every one of these movies have the cars, planes anything that has a motor and wheels just stops. Also you would think that they had 15 yrs to explore their surrounding for useful things they could use. But it show the girl acting like that was something new she just found close to home, the RV. And then they showed the homemade medicine for the boys Asthma. All in all it starts out OK.