Unlikely the murderers will get 1 to 2 years of coomunity service. I have never once seen a major person felony be given anything less than hard time.
However, the murders are juveniles which throws a major monkey wrench into it. I don;t know how PA works, but here, thse kiddos would first go through an extensive hearing to see whether the kids are mentally matured enough to be tried as adults. This measures alot fo things, mainly whether the kids knew the consequences (total BS in my opinion. Any 10 year old or older, save mental disability, knows that if you kill someone they die) and if they are mature enough to aid and assist in defense in adult court. If they are deemed unready they will be tried in juvenile court adn could face jail time up to the age of 25. In the highly likely chance they pass the mental hearing, they would go to adult court and be tried as adults, with everything but the death penalty (I belive SCOTUS denied it for any defendant under 18) on the table.
And yes, I have seen a 13 year old be convicted of murder in an adult court and get life w/o parole.
If found guilty, it is likely the least they will get is about 10 years, and that is only if they are left in the juvenile system. But, then again, I'm not familiar with PA criminal law or PA Juvenile law.