Though they were both just teenagers.To stop Uchiha clan's on turning back on the village and the Hokage getting rid of the Uchiha's in return. One of the most talented Uchihas, son of the head of the Uchiha Clan and the granddaughter/son of the Hokage itself got an arranged marriage.

after every paperwork was done, Itachi and Starie were officially married which wasn't exactly great for neither of them, they argued and fought everyday and was cold to eachother, and that was a problem