Well - i count them as 2 -
think about it (whilst your answer is also correct) but...
The child is 'ill' - it uses/drains resources from its mother - thus she (theoretically) should be allowed 'larger' rations to compensate for her bioload.
Also - is the child contagious? - what is the illness? would it pass? would the child be permanently damaged from it?
A nuke bunker is an enclosed environment - its exactly like a fishtank - whatever goes in to a creature - comes out and needs dealing with - anyone who has had kids knows how much 'mess' they make - also - air is a consideration - screaming kids - possibly running a fever etc - let alone the stress on the other people.
Like a fishtank - what ever goes into the system - stays in the system - just transformed - problem is that the output is often toxic.
Of course - I could then say kill mother and child - kill two birds with one stone so to speak - and keep the little sister alive in the mom n sprogs place

Of course - there is plan C - play a lottery game
