Morrigan had a cunning plan. Knowing Don Salvatore's liking for barbecued fish fingers, before the party she had poured a whole can of lighter fuel inside the barbecue, intending that it would catch fire as soon as it was lit.
To distract Don Salvatore and Benjamino, she started to flirt with the butler, Abne. Don Salvatore, of course, picked this up and he immediately fired him.
And to shock Benjamino, who had not missed the interaction with the butler or with Don Salvatore, she asked him to just be friends. So he told her he would move out as soon as the party was over. That, and the announcement that he would not be following his father to the top of the Criminal career, was quite enough for him. He knew very well that there could only be one Emperor of Evil, and a lifetime of experience had convinced him that he could not trust his brother where ambition was concerned.
The barbecue, neglected while all this domestic drama was playing out, naturally caught fire.
As did Don Salvatore, as Morrigan had intended.
For a moment there seemed to be someone else there in the flames.
Abner heroically extinguished Don Salvatore. "Abner, you're hired back, and you get a big raise. I can't do without you!"
The fire was so intense it spread into the kitchen and Benjamino got rather badly burned, but Don Giovanni scooped up little Salvatore and ran outside.
The firefighter arrived and saw the Grim. "Who was it? Don Salvatore?" But the rigged barbecue did not kill Don Salvatore, per Morrigan's plan.
Morrigan, watching from safety outside with Morgause, "I think your Granpa has been burned, Morgause. Where's Morgaine?"
"She climbed up on the roof to get away from the fire."
Abner, knowing the truth, came out first.
"I feel sorry for you, Morrigan. You are a user and you will always be evil to the core. You deserve everything you get."
She saw, through the kitchen door, a firefighter, Salvatore, who had aged up to toddler in the middle of all this, and his grandfather, the Grim... then who is the Grim here for?
Sadly, it was Morgaine who died. She had climbed onto the roof to escape and the firefighter declared she must have died by inhaling too much smoke.
Morrigan was devastated.
In the aftermath, Benjamino simply took Morgause and moved out. Thoroughly shaken by his experience, and lost in his grief for his little girl, he moved away with Morgause to a small house called Rhapsody in Blue, on the outskirts of town.
Benjamino's hair and eyebrows were mostly burned off in the fire, so he took to wearing a beret and was determined to get really fit again.
As soon as he heard about this, Giovanni moved back in with his father and Morrigan.
Don Salvatore was finally able to buy out the criminal base, and now calls it Renzella Import-Export Enterprises. He sacked Benjamino, and Elvira, who he still regarded as responsible for his earlier death as a vampire, even though he had asked her to turn him.
Don Salvatore refused to give Benjamino any money as he was taking away his only remaining beloved granddaughter. So Benjamino had to get a job in Athletics to support himself and little Morgaine.