At the Tevatron, heavy t'→ bW decay is currently being searched for, but a broader spectrum should be explored at the LHC. We discuss the two branches of b'→tW(∗) and t(∗)W for b' below the tW threshold, and how it merges with b'→tW above threshold. We treat with convolution method and five body final state. A similar discussion is given for b'→t'(∗)W(∗) decay, and t'→b'(∗)W(∗) decay, besides the t'→bW considered by CDF.