We are taking a stroller for DD4 and DS2, but my dad loves to carry the kids on his shoulder so they can see. Since that gets crazy tiring, we got my dad this for Father's Day. I think they're going to love it, and it might work for you:
http://piggybackrider.com/
Kristen
http://piggybackrider.com/
Kristen

Also perhaps because I am short and my DD's are tall.... but they were NEVER stretched straight up at full extension. 
Whoever manufactures the child 'tethers' should totally make a commercial with kids on the moon!


