Why shouldn't he be? 
( Why ( ( ( ( should n't ) he ) be ) ? ) )
(ROOT (SBARQ (WHADVP (WRB Why)) (SQ (MD should) (RB n't) (NP (PRP he)) (VP (VB be))) (. ?)))
There is no reason he shouldn't be.
( There ( ( is ( ( no reason ) ( he ( ( should n't ) be ) ) ) ) . ) )
(ROOT (S (NP (EX There)) (VP (VBZ is) (NP (NP (DT no) (NN reason)) (SBAR (S (NP (PRP he)) (VP (MD should) (RB n't) (VP (VB be))))))) (. .)))