Is it permissible to place a lock of hair from a deceased daughter in her mother's shroud, and will the one who does so be punished for it?

Placing hair with the deceased in their grave or shroud is an innovated matter and not from the Sunnah, whether the hair belongs to a relative of the deceased or to someone else. The deceased gains nothing from this hair, nor does anything benefit them except their deeds, by the mercy of Allah the Almighty. It is incumbent upon the one who does this to seek forgiveness from Allah the Almighty and to avoid such actions.