I know it is difficult to sell something that becomes part of your life, but in your situation that might be the best option.
First, Catalinas are generally good boats and I would not hesitate to take one out in the ocean. I would be careful to pick relatively moderate
weather, especially with the smaller Catalina.
The other thought, a 28' boat is a bit small for 5 people. Of course that is very much a matter of personal preference and your ability to adapt to a small space. I met 2 couples from
Germany that were very happy all cruising the
Caribbean on a 27' boat and I have met a
single couple that thought 40' was too small.
If you do get around to circumnavigating with the whole family 28' could get small for pretty much anyone. You might consider starting out small,
learning what you want and need on a boat and later upgrade to a larger boat when you get ready for more serious cruising.