Prison officer vetting / Social media check form

hi Guys im 4 week into vetting since i filled out onboarding form. just recieved form for all social media i share facebook with my wife as i deactivated mine due to my current job hopefully wont be a problem do they actually access your facebook and messages or just what the public see if searched for also i found out that my wifes nephew that we never see as he is estranged was recently jailed and is on probation so i have informed them of that hopefully that wont hinder me

cheers
Russ