She said the move had been beneficial - but did present a challenge when the family travelled.
"It's not doing you any favours, and it can build a lot of resentment," Marshall said.
"So, we sleep separately, and I love it! Expensive on holidays, though."
Zoe and Benji welcomed daughter Ever in June last year, joining 4-year-old Fox.
Zoe spoke out following Ever's birth to reveal she was suffering from "post natal depletion".
"It got me. I'm depleted. I got the bloody post natal depletion!" Marshall shared on Instagram. "I thought I could outrun it. But it got me.
"Here we are. On and off since she was born. I know moving states, quarantine, lockdowns, etc don't help. This overwhelming feeling, it's exhaustion. Then getting sick, just the sniffles or a cough but it lingers, for months. Then getting frustrated because I'm missing out on getting out because I'm so exhausted."