I obviously echo that sentiment but your information isn't quite accurate.

Just off the top of my head, there was a 2021 fatality in Perth at Freemantle Port Beach, then two at Cottesloe- one in 2011 and another in 2000.

From the GSAF database there are six cases of boys bitten by sharks at Myrtle Beach between 1986 and 2010. Each received puncture wounds and/or cuts/lacerations, but none of the cases involved a leg amputation. Your family might have been right to be skeptical...