Our family is very close but spread across different states. When videochat doesn't hack it anymore, we travel. We try to travel with the larger (around 20 people) group mixed with adults and children, and create memories. This is my experiences of how to save money and how to accommodate with a large group ranging from all ages.
I recently booked a trip for my whole immediate family of 5 in a beachfront VRBO for 4 days, and spent less than a friend who spent 1 day/night at Waterpark Resort with the same number of children. It is important to be aware of price hikes during Spring Break or other holidays and take those into considersation when booking. My immediate family met up with the other family and soon we were a group of 20 again.
My mother is a Filipino woman who loves to cook. When the large group of us gets together we find a place, where we can cook or grill out. Grocercies on hand, and food that we all love. We always try to have one meal a day with the large group. During other times of the day we will split up into our smaller families and try places/activities we desire.
Nature is free. Enjoy it. Take the time to enjoy hikes, fishing (check fishing liscense requirements), parks, animal rescue centers, and the beach. If everyday has an admission required activity, for large groups the price can add up quickly. Get creative and find family enjoyable activites that everyone can enjoy for FREE.