Physical Welfare of Children vs. Your Calling

Here is a question I have for you. Should the physical welfare of your children take the precedence in your life over your calling or occupation? The reason I ask this is because I have been reading a lot of missionary stories lately. In one of them,(the story of Jonathan Goforth - a fascinating story (p.s. isn't that a great last name for a missionary?)), out of Jonathan's eleven children born, five of them died in China due to poor sanitation and diseases that were present there. So it got me to wondering. And I don't know what the answer is. Some people would say he and his wife were neglectful. On the other hand, they reached thousands of people in China with the gospel which they wouldn't have been able to do so if they had not been there! It used to be popular back in the day for missionaries to send their children to boarding schools (which was the case in Eric Liddell's case - he was sent to a Scottish boarding school while his parents were in China. He was the athlete who refused to run in one of the Olympic races that took place on Sunday. He then won the 400m race that took place on a different day. He later became a missionary to China as well, another INSPIRING missionary story). Putting missionary children in boarding schools is no longer popular for obvious reasons. Children need their parents to raise them, not some headmaster! But I still wonder if it is right to place your children in a dangerous environment. I also read a book on Nate Saint, one of the men (along with Jim Elliot) who was murdered by a savage tribe in the amazon(?) jungle in South America. I was wondering if they should have exercised greater care in their plan to reach that particular tribe who was known for being cannibals. Is it wrong to wonder such a thing? I think someone will probably respond and tell me that my questions are down right heretical. I do know that as a result of their deaths, in that particular tribe many people became Christians at a later period in time, in a large part due to the missionaries' witness. But I couldn't help feeling terribly sorry for the wives and children who were waiting at home in vain for their husbands and fathers to come home (five missionaries were murdered in that instance). On the other hand, many missionary wives know in advance what they are getting into (although the children do not have much say). And I know it is easy for me to say as I sit in my comfy chair "They should have been much more careful...etc." Maybe I should ask a missionary and see what they think. Or maybe the answer varies from case to case. Anyway, the reason why I am reading so many missionary books is because I am on the hunt for inspiring Christian stories for children and I found these in our church library and enjoyed them all.