If it will not harm you to do so, I cannot see how it will hurt to make an attempt. The shard twists magic- not even Compassion and I are able to restore her to how she'd been before. Perhaps you might be better able to see it done.

[ There is only so much they might do- but Galadriel's skills and power are fundamentally different. Perhaps it would be enough to see Sina restored. ]

It was no burden. It is Compassion's purpose, to ease pain, to mend. Sina...is a friend. To do nothing- that would have been a burden.