sentences:  Maerten and his brother, also called Pieter, first trained with their father.A pupilage with the leading mid-16th century leading history painter Frans Floris has been surmised by some art historians but there is no documentary evidence for this.As a trip to Italy had become a rite of passage for Flemish artists in the 16th century, de Vos travelled to Italy where he resided between 1550 and 1558.