If you have a friend with spaces that you could suggest to them that might help them. Taking a week here and there is one thing but most people can not just take a month off work either and for each parent to take 2 weeks leaves them with no family vacation time so I can see that they are upset. Nothing much you can do about it. Do be prepared for some of your clients to find another daycare that can take the child for the month and then when you return have them decide not to come back at which point there won't be much you can do either.