He may have also elevated his son to co-emperor during the last days of his reign , but this is disputed .
He elevated his son , Tetricus II , to caesar in 273 to increase his support .
Tetricus II may have also elevated Tetricus II 's son to co-emperor during the last days of his reign , but this is disputed .
He elevated his son , Tetricus II , to caesar in 273 to increase his support .