If Theo was born after Will was born, then how many sequential orderings of the children, from firstborn to lastborn,...

I don't understand how there can be two possibilities rather than one. The problem allows us to conclude that U(R) is born in 1993 and S(L) is born in 1991. Here's my setup if T is born after W(who is born after Z). (L) ___ S ___ T. ___ W. (3 lefties) (R) Z. ___ ___ U. ___ ___ ___. (2 righties) 90. 91. 92. 93. 94. 95. 96. What am I missing?