I'm not sure that I agree. Im not sure how many holidays you take each year, but, if this is your main family holiday then I think that it should stay that way. Maybe ask your husband to suggest that you all go away a little later in the summer for a long weekend or something. I appreciate that your husband wants him to be happy but holidays really are precious times. If you have a typical busy London life my personal feeling is that every family needs a little together time away from it all.