Reese Witherspoon is looking back at her early days of motherhood.

The actress, 45, joined Dax Shepard’s “Armchair Expert” spin-off “We Are Supported By” and opened up to Kristen Bell and Monica Padman about welcoming daughter Ava, now 21, in 1999.

“I did not have a lot of support with my first baby and I learned really early, like this is not going to work,” she recalled. “I tried to muscle through for five months with Ava, just not sleeping and I became delirious.”

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Witherspoon welcomed Ava two months after tying the knot with ex-husband Ryan Phillippe. They welcomed son Deacon, 17, in 2003 before divorcing in 2006.

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After welcoming Ava, Witherspoon said there was no way she could have worked, revealing “I was lucky enough to have money saved and I didn’t have to work, but it’s just not a one-person job.”

Adding, “I would even say it’s not a two-person job.”

The “Walk The Line” actress is also mom to son Tennessee James, 8, whom she shares with husband Jim Toth.