We cruised the Ruby last Easter and we had the same questions for our 8 year old daughter. the kids staff put on an easter egg hunt, decorated eggs, and did other crafts during a holiday fare. The culinary staff made some exquisite egg sculptures for Easter Sunday. We stopped at a dollar store a bought a few of the plastic eggs prior to leaving and did a egg hunt in the room. We also brought a small Easter Basket in our luggage.
They did have a soda card with some add ons. The basic package was around $25. Options to add on ice cream and milkshakes cost more.
We used the laundry facilities as well. There are bill changers for coins. The washers are large and very clean. Loads were about a dollar and soap was the same. They were very nice after a port day with wet bathing suits that never seem to dry in the room.
You will love the ship. We were so impressed with Ruby and the Princess line that we are booked on another 7 day later this April on Star Princess.
Enjoy your trip,