And so? Jealousy does not preclude saying "enough is enough!" She has already provided support before. There are ways to prevent pregnancy. Sometimes they fail, but not FIVE TIMES.

The couple's own choices led to the situation. She already had four children. She or her husband could have taken the responsibility end the likelihood of pregnancy by one form of surgery or another. Pretty sure the sister would have been glad to help pay for that.

Not from jealousy, but from realistically assessing the situation. Someone has to be the adult here, and so far she's the only one in the family doing so.