Visited a friend of mine in Cavite over the weekend and found out that due to financial incapabilities, her sister agreed to have her child adopted by one of their closest relatives. If you are in her sister's plight, would you have done the same?

Could be good, could be not so good. In the first place, they should clarify the situation, to that "close relative" of theirs. Maybe it could be the easiest idea they could think of for the moment. But if I were the sister, I would just ask for help instead of giving the whole responsibility to other members of the family.