If you have seniority, flying with children can work well but if not it can take a heavy toll on your family and personal life. I have just had to resign as I just couldn't work the weekends any more and be away from my kids. You really do miss a lot and they are only kids for such a short time. Things like, helping out with homework, after school activities, kissing them good night, being there when they are sick and just just want mum, weekend sport and family time rarely exits. The nanny was becoming the mother. I LOVED flying but my children will always come first. Good luck and I hope it can work for your friend.