A 3 month old and a 5 year old? Lord Almighty...
While I don't support the death penalty, I certainly understand why 7 states had one for this type of offense involving children under 12, before the Supreme Court knocked those laws down some years back as "cruel and unusual". These crimes are very depraved, and most cruel and unusual in and of themselves when they involve little children! Maybe be should re-examine just what is "cruel and unusual" today. 
Time to step on these types of crimes hard, hopefully these shorteyes get theirs when they hit the joint! We as a society shouldn't even waste the time with rehabilitating someone who does this crime to little children. 
Society should just go Biblical on them, tie a millstone around their neck and throw them in the sea! Even Christ, when saying this, couldn't bring Himself to forgive them, why should we?
As a father of 5, grandfather of 9, this crime is more than heinous enough for the death penalty, even though I don't support it!