I am not sure how your planbs work out-but i would have some seperate rucksacks for all the family-i would give your wife a similar size pack to you and give your children(if you have any) very small day sacks!

I would use a technical outdoor sack-have a look at www.karrimor.com

they come highly reccomended-own a number of thier sacks-i am not sure if they available in the usa!-I'VE just checked and they do-

Karrimor North America Inc
239 NW 13th Avenue
Suite 211
Portland
Oregon 97209

USA
Contact: Larry Olmstead
+1 503 242 3551
+1 503 242 3561




Mark