My 2 year old knows when daddy uses his serious voice and says hush she knows its time to be quiet and or to whisper. We bought a collapsible wagon from SAMs that has large plastic wheels with a large rugged tires and lots of room. I know it will handle at least 120lbs because my daughter and three nieces ride in it almost every time we visit the zoo. I have a bag molle to the rear that hold snacks and waters for the kids.
http://www.samsclub.com/sams/folding-wagon/prod3080161.ip?mobileredirect=false
http://www.samsclub.com/sams/folding-wagon/prod3080161.ip?mobileredirect=false