…by the flippant answers, CC: it is a bit of a naive question, but you have gotten
some useful feedback.
The sexes and ages of your four
kids, and who could possibly bunk with whom, will determine many of your requirements WRT size/displacement and accomodation. You might need to make some modifications to create more suitible
offshore berths. The forpeak's pounding and general motion often makes for a pretty uninhabitable space while underway.
Keep in mind that a large boat may take more than two crew to handle: how many kids can take on serious responsibilities like
steering, handling
docking lines, trimming
sheets, etc?
There are many families who have done it, and lived to write about it. Some cruisers have even had
children along the way. You might try some pertinent terms in a search
engine: I just got a page full of hits.
Good Luck.