Background information and notes Edit
Jonah never appeared on-screen; his gravestone was seen in 614.
Since Jonah must have been born between June 16, 1839 and June 15, 1840, the most obvious candidates for his parents are Gabriel Collins and his wife Edith Collins. Keep in mind these two hardly mentioned any of their offspring. If Jonah were a sickly child (likely given his short lifespan) then it is quite likely he was in the care of nurses somewhere. His name is Collins so his father almost certainly must be one of several individuals: Daniel Collins (which seems very unlikely given his mental state and the way he's watched over), Desmond Collins (which might be possible, but there's no hint he has any offspring at this point, or even a girlfriend), Tad Collins (which is biologically possible, but we don't see any hint of such behaviour at the time), or Gabriel.