Trajan Decius elevated his son 
Hostilian to co-emperor in 
251.  He was apparently much younger than his older brother 
Herennius Etruscus, and did not have much power; his mother Herennia Etruscilla acted as regent.  Hostilian died of 
plague after his father and brother died in the 
Battle of Abrittus.  This solved the minor succession crisis created when the army proclaimed 
Trebonianus Gallus emperor.
 
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