All donations are per family, and carry on down through the generations.
Example 1:
Gen 1 donates 10000 (total is 10000)
Gen 2 donates 10000 (total is 20000) -> he can get a gift from the king
Gen 3 donates 50000 (total is 70000) -> he can get a gift from the king
Gen 4 donates 10000 (total is 80000)
Gen 5 donates 50000 (total is 130000)
Gen 6 donates 10000 (total is 140000)
Gen 7 donates 60000 (total is 200000) -> he can get a gift from the king
Gen 8 can not donate because the maximum total has already been reached.
Example 2:
Gen 1 donates 200000 (total is 200000) -> he can get 3 gifts from the king
Gen 2 can not donate because the maximum total has already been reached.
All gifts from the king remain in the family (on your Tamagotchi) and are passed down through the generations.
When your adult Tamagotchi character returns to Tamagotchi Planet, leaving her/his baby in your care, they take most of the souvenirs with them. However, they leave all the gotchi points, and purchased meals / snacks / items. The souvenirs that are left behind are: all those given by the king, travel souvenirs, and the movie posters.