Tarquin (Tarkin) is also the name of Grand Moff Wilhuff Tarkin in Star Wars, the Commander of the first Death Star. Not really the greatest association.
This is the name of the last prince of Rome and rapist of Lucretia, the daughter of a prominent man and wife of a governor. Lucretia's rape and subsequent suicide led to a revolt that brought about the end of the Roman monarchy and the beginning of a republic. This story was popularized in Shakespeare's "The Rape of Lucrece". Due to its historical context, not a great name for a child.