The Secrets of Alistair Ambrose

When the Oliver, River and Clarissa decided to accompany Lucretia to Kesgrave over their first summer break, Lucretia gave them only one rule: don't snoop around or open any locked doors. So naturally, it took less than a week for the rest of the party to go snooping around. After uncovering a few shadier elements in the back room of Ambrosia, the group unlocked a basement study filled with unsettling artifacts and dark magic spellbooks-- and an old skeleton chained to the wall. River was compelled to scream and panic as soon as she touched one of the books on the wall, and Oliver found Darktongue letters sent between Alistair Ambrose and other key names: Seraphina Onyx and Marius Conwyn. After the ruckus they caused, Lucretia and Alistair were alerted to the snooping and quickly ushered the group out of the study.
Alistair decided then to confide in the party, knowing that their suspicions would continue if not told the truth: he is a lich, who through magical means has hidden his true nature from the world for years. He completed this ritual after Lucretia was born, but before the Realignment; he was driven both by an intense curiosity and his intense love for his husband Lucius, who as an elven vampire would long outlive him otherwise. He did not go into detail as to how he accomplished this foul ritual, but since completing it he has had to kill to survive. He assured the party that this is not a frequent occurrence, and when it does need to happen the Brightspears bring him only the worst kinds of people to "feed on". 
The two letters that Oliver found had very different tones. The first, from a Marius Conwyn, was friendly in nature and seemed to deal with shared research/information. The letter from Seraphina Onyx, on the other hand, was a call for solidarity for Alistair in something soon to come. Alistair told the party that she was planning in some way to grow support for necromancy/dark magic using her political station in Vanshire, but seemed to think this plan would be fruitless.
While Alistair did not reveal anything about his phylactery, Oliver's Sense Soul spell revealed that there is a connection between Alistair's soul and Lucretia; whether she carries his phylactery or she herself is the phylactery is unknown.