Diagonals of Quadrilaterals

Part 1

ABCD is a parallelogram and Point F is the point of intersection of the diagonals of the parallelogram. The lengths of segments AF, BF, CF, and DF are shown. Drag any of the blue vertices to change the shape of the parallelogram. What do you notice?

Part 2

PQRS is a quadrilateral, and the diagonals of the quadrilateral intersect at Point T. The lengths of segments PT, QT, RT, and ST are shown. Drag any of the blue vertices to change the shape of the quadrilateral. Does the relationship you noted in Part 1 hold for any quadrilateral?