The parents of a girl with 'childhood dementia' have revealed why they felt they had no choice but to terminate their much-wanted second pregnancy after discovering their unborn child also has the disease. Leni Forrester, now two, was born seemingly healthy to parents Emily, 33, and Angus, 35, from London. But when a close family member underwent genetic testing six months ago, their lives changed forever when results showed the family carried a recessive gene which can cause Sanfilippo syndrome, a rare genetic disorder dubbed childhood dementia. The degenerative disease causes children to gradually lose all the motor skills they've...