Will the questioner bear the sin of her friend, who taught her masturbation before puberty, and who she later learned committed an abomination?

If the act occurred before puberty, there is no sin, based on the Prophet's (peace be upon him) saying: "The pen is lifted from three... and from the child until he reaches puberty." However, if it was after puberty, it is a grave sin, and inviting others to it incurs upon you a burden of sin equal to that of those who follow you, based on his (peace be upon him) saying: "And whoever calls to misguidance will bear a burden of sin equivalent to the sins of those who follow him." Nevertheless, sincere repentance to Allah is obligatory, and she must visit her friend and advise and admonish her gently to encourage her to repent and return to the straight path.