Gustav's father Magnus left Sweden in 1578 when he was expelled by King John III for beating his wife.
In 1590, Gustav was expelled from King John's court because of excessive behavior in the taverns of Stockholm, which led to his mother's intervening on his behalf with a plea to the queen, Gunilla Bielke.
Sofia's income was in danger, but the issue was solved when King Charles forced him to return the fiefdoms, which were given to his mother.
In the conflict between Sigismund III Vasa and Charles IX, Gustav sided with the latter and was put in charge of Kalmar Castle on 8 June 1597.
[1] Gustav never married, but had an illegitimate child with Ingrid in Halkved: Source: Riksregistraturet B:90,1600 jan-juni, f 73v-74r, 1600 den 3 April: [f 73v:]