I'm more agast at the sexism in a "husband wife business trip that is good for his career." Wow! 1962, anyone? What if you had your own career and couldn't take the time off?
Another option would be to bring the kids and nanny with you on the trip. Put the kids in their own room. With this sort of arrangement, you may be able to hire an older teen or young adult (though with a 13 year old son, maybe hiring a grandmotherly type is more appropriate anyway).
I agree with the people who are less worried with a 13 year old at home. With him around, what you really need is someone to care for your four year old and make sure your older son doesn't get into trouble. But your 13 year old is old enough to know if something is wrong and if you make sure to leave instructions to contact a responsible adult, they'll be fine.
Another option would be to bring the kids and nanny with you on the trip. Put the kids in their own room. With this sort of arrangement, you may be able to hire an older teen or young adult (though with a 13 year old son, maybe hiring a grandmotherly type is more appropriate anyway).
I agree with the people who are less worried with a 13 year old at home. With him around, what you really need is someone to care for your four year old and make sure your older son doesn't get into trouble. But your 13 year old is old enough to know if something is wrong and if you make sure to leave instructions to contact a responsible adult, they'll be fine.