American actor and musician, born 1954 and known as Will Robinson in Lost in Space and Lennier in Babylon 5, who played the engineer Kellin in Deep Space Nine's The Siege of AR-558.
Bill Mumy is an American actor, musician and writer who began working as a child, notably in The Twilight Zone episode It's a Good Life and as Will Robinson in the 1960s series Lost in Space. In the 1990s he played the Minbari aide Lennier throughout Babylon 5.
He appears in Star Trek once, in the seventh-season Deep Space Nine episode The Siege of AR-558. Mumy plays Kellin, a Starfleet engineer among the worn-down troops holding a captured Dominion communications array.
Kellin works with Ezri Dax to expose the hidden subspace mines surrounding the position, and is killed during the final Jem'Hadar assault while protecting her. The part let Mumy play a human rather than an alien under make-up.