How cute! My sister's kids are the same age as mine (2 yrs apart) but I have 2 boys and she has a boy/girl. My nephew would arrive with a back pack which contained pajamas, toothbrush, clothes for 2morrow and TOYS. My niece arrived with her pull along Barbie luggage, 3 changes of clothes, nail polish, dolls, hair bows, etc. lol. Make some cookies (even ready-to-bake, but they decorate), or popcorn or microwave s'mores -graham cracker on napkin/plate, big marshmallow on cracker. zap 10 seconds (try that first), then add chocolate and other cracker). Careful, hot. Board games or memory match card games. Have circle story telling- you say, once upon a time... the next one has to say a sentence... there was a frog... etc. the stories get outlandish and silly, but that's the point. Sleep in sleeping bags on the living room floor. Most of all, they will all relish your undivided attention no matter what you do! The first time we took the boys to Disney, they told everyone about the amazing pool with an alligator and jumping from bed to bed at the hotel. Seriously. :-) It's the memories you create, not always 'what' you do.