The buyer recently listed her half-floor luxury apartment in the Eureka Tower skyscraper in Southbank with a price guide of $8.8 million.
Jreissati, who is general counsel at Bensons Property Group, chaired by her father Elias Jreissati.
Australian businessman Graeme Samuel has sold his former Toorak home.
The now Brighton-based former consumer rights chief was seeking $8 million to $8.4 million for the single-level home which was created by building designer Kim Andrews and John McNamara.
The former competition watchdog sold it to Samantha Jreissati who seeks to accommodate her growing family.
The buyer recently listed her half-floor luxury apartment in the Eureka Tower skyscraper in Southbank with a price guide of $8.8 million.
Jreissati, who is general counsel at Bensons Property Group, chaired by her father Elias Jreissati.
It sits in 855 square metres of landscaped gardens by Jane Jones that feature a swimming pool.
Samuel paid $3.05 million in 2007 before its full scale renovation.
It was owned in the 1970s by media executive David Evans who sold his nearby home, Koonda last month.