"As has been widely documented, housework and childcare demands fall on mothers significantly more than fathers regardless of children ages. Less well-known is the fact that housework and childcare time demands remain high even when children enter school and can be constraining for women who spend as many as 7 hours with children above 6 years old."
https://blogs.lse.ac.uk/politicsandpolicy/the-persisting-pay-gap-and-the-motherhood-penalty/