Jennifer Garner admits she is a ''fun-killing'' mom.

The '13 Going On 30' star - who has Violet, 13, Seraphina, 10, and Samuel, seven, with her ex-husband Ben Affleck - has revealed that although she is a strict party-pooping parent and gets called ''the dragon'' by her brood, once a year she has a 'Yes Day' where her kids get to do as they please.

Appearing on 'The Tonight Show starring Jimmy Fallon' on Thursday (12.09.19), she confessed: ''If you're like me, I kill the fun.

''I am so lame. I say no to everything. They call me the dragon. They have all these names for me.''

However, the 'Peppermint' star admitted it can be a difficult for her kids as they have to agree on what they want to do on the annual free-for-all.

She added: ''A 13-year-old and a seven-year-old have a different idea about what they'd like to get out of 'Yes Day'.

''They have to agree 'cause it's just one day.''

Jennifer then quipped: ''The one thing they can agree on is basically making an a*s out of me.''

The 'Daredevil' star recently admitted that she has become more ''chilled out'' when it comes to motherhood.

She said: ''I can't really complain about my kids. They're pretty awesome. They humour me. But I have chilled out and stopped trying to be my mom.''

And the 47-year-old star plans her work around her family now.

She added: ''It used to be [just] what you can get, first. You're just so grateful to have a job, and leave the restaurant. And then it's what job would fit in the hiatus of Alias, and be just something different from what I was doing nine months a year. And then it became about how to surprise myself. I'm always driven by writing, so I do quirkier movies more than big, bold ones. Then it became about my kids' schedule, and being pregnant and nursing and where my husband was working, and how to fit it all in. And now it's whether they can shoot in L.A. while my kids are in school.''