Famil Reunion

Planning a Family Reunion and would appreciate simple table decor and theme ideas.
Would like the theme to evolve around the idea of Family Heritage/Family Tree. Have many ancestor pictures and memorbilia that I would like to incorporate.
Would also like to keep it with a picnic-type feeling.
Any ideas to keep the kids entertained indoors in a limited space. Like a craft table,,?? Any simple craft ideas for kids that range in age from toddler to preteen??
Appreciate any imput!!
Thanks,
Susan