It would depend on the relationship and how they would behave.
If it were my parents, I would do it if I felt it was necessary as they would honestly want to help.
However, I would not do it with my FIL as he would believe it is something that he can hold over us.
Personally, I don't think I would do it generally as I would feel that I was taking advantage. I will not behave like my sister (whole different story there).
yes I would and yes I have. My MIL lent us a lot of money at one point and we intend to pay her back with interest, but obviously she would have made more money if she had put it in the bank. It's been 2 years now and we are still years away from paying her back. I know it made her happy to be able to help, and without the help we would have been in a fairly dire situation.
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