Luke, if that's the case, then you really should notify whoever your Dad left his creative estate in the care off (I am sure your Mum would know) As when a writer passes away, their 'estate' (someone they chose and mentioned in their will - it doesn't have to be family) is the owner of all the creative works they made in their liftetime. When I pass away my husband or my daughter will be granted creative control of my novels...