The 'Big Little Lies' star is currently at home with her husband Jim Toth, their seven-year-old son Tennessee and her two kids Ava, 20, and Deacon, 16, and though things are going smoothly at the moment while they all avoid going out where possible due to guidelines to minimise the spread of coronavirus, she knows that could change.
Speaking on Miley Cyrus' 'Bright Minded' series, she said: "I try to be patient and they try to be patient with me, but we're only on day 11. I don't know what's gonna happen."
Reese has found it vital to "designate space" for each member of the household and respect their wishes if they ask for privacy.
She said: "I think it's really important to designate space. My husband and I are both working from home and all three kids are doing school online. So everybody has a room that has a little area and there's a privacy sign there, so when the privacy sign is on and your headphones are on, you can't interrupt.
"You have to have rules ... It's really important to post them on the wall for your family, just so we respect each other's space."
The 'Little Fires Everywhere' star has also been in regular contact with her friends.
She said: "I have like five girlfriends an d I'll just text any one of them. We try to connect every day."
Reese explained Tennessee is thrilled to have everyone at home, but Deacon is missing his girlfriend and Ava has had to return home from college and do her studying on line, and the 44-year-old actress understands why that isn't easy.
She said: "I think a lot about people who are coming home from college.
"That's a time when you are trying to individuate. You have to actually kind of move away from your parents' ideas, you have to move away from their structure, their routine, create your own. And now you're having to go backwards. And that must be so frustrating to lose that independence."