yes, to me too more probably one of the elder chicks is gone

Justyna answered to someone it was the youngest one - Nr 4.
We will see what is the opinion of prof. PZ - but it is not important in my opinionT
Three chicks will have better chance always.
at 14.20 (no feeding)

the behaviour of the littlest chick is to me more typical for the "hatchling" (the two are already typical nestlings)