- sit for someone
- sit for someone1. to care for someone in the role of babysitter. •
I sit for Timmy sometimes. I like him. He's a good little kid.
•Mary doesn't sit for anyone anymore. It leaves no time for a social life.
2. to serve as a babysitter in someone's employ. •I sit for Mrs. Franklin every now and then.
•Ted used to sit for the Wilsons.
3. to serve as a model or subject for someone, such as an artist. •She sat for the portrait painter every day for a week.
•She is looking for someone to sit for her so she can develop her skills.
Dictionary of American idioms. 2013.