Reese Witherspoon's daughter is a ''second mother'' to her son.

The 'Wild' actress is pleased 15-year-old Ava and 11-year-old Deacon - her kids with first husband Ryan Phillippe - dote on their little brother Tennessee, two, and she is finding raising her youngest son much easier than when she had Ava.

Reese - who is married to talent agent Jim Toth - said: ''The older kids love their baby brother.

''My husband and I prepared them for him by talking about the new baby coming along and being open to hearing their thoughts about it and these days they all get along just great. It's really sweet to see them in their new roles as older siblings and mentors.

''Ava in particular is a great help, which makes it much easier for me than it was when the older two were small.

''When I had Ava I was only 22, I didn't have any help and my mother lived in a different state.

''So now, with Ava helping with the baby-sitting and the bath-giving, I feel like the baby has a second mother around helping me out.''

And Reese needs the extra help because Tennessee ''rules the roost'' at home.

She added: ''It's just as well [Ava helps] because the baby is very bossy - he talks all day, he rules the roost and the rest of us just do what he says.''

The 'Hot Pursuit' star says nothing makes her laugh like her older kids.

She told HELLO! magazine: ''They're the funniest people I know. My 11 year old will do anything to make people laugh - he dances, he sings, he does funny voices, the works.

''My daughter is more intellectually funny. She's 15 and writes funny things. She's really very witty. Between the two, we have all bases covered.''