The one-time world No.3 turned doting tennis mum followed up her third-round elimination of fourth seed Jasmine Paolini with a straight-sets win over Veronika Kudermetova on Monday.
After falling behind 4-1 in the first set, Svitolina took full advantage of an unfortunate injury to Kudermetova to power past the wounded Russian 6-4 6-1 on Rod Laver Arena.
The Ukrainian's reward is a last-eight showdown on Wednesday with either sixth-seeded 2023 Open runner-up Elena Rybakina or 2022 AO semi-finalist Madison Keys.
Now 30, Svitolina is playing some of her finest tennis and credits a happy family life with her veteran tennis-playing husband Gael Monfils and two-year-old daughter Skai for helping take her through to another Open quarter-final.
"I feel 2019 was a long time ago. So many things happen," she said.
"It was a lifetime ago. Having our daughter, Skai, and then surgery as well.
"So I'm really pleased with the performance throughout this tournament and just really, really enjoying this win today."
Monfils plays American Ben Shelton later on Monday also striving to make the quarter-finals after also ousting the men's world No.4 Taylor Fritz in the third round.
"I have time, a little bit, to do my recovery and then we will be all energy to watch his match and it's going to be an epic one, I'm sure," Svitolina said.
Going for broke, Kudermetova had raced out to her 4-1 lead in the opening set after breaking Svitolina twice in the first five games.
But the Russian quickly found herself 5-4 down after conceding four straight games, and then needing a medical timeout for an abdominal strain.
Svitolina showed great foot speed and deft touch to run down a Kudermetova drop shot and deliver a lovely cross-court winner to bring up three set points.
The 27th seed only needed two as Kudermetova fired a forehand long to hand Svitolina the set before taking a bathroom break to reset.
But nothing could stop Svitolina from progressing to a 12th grand slam quarter-final.
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