10-yr old daughter lying

My 10-yr old daughter has had history of stealing & lying.  The last time she did it was beginning of the year.  Since then I've been monitoring and spending more time with her and she has improved in her behavior.  Her grades are getting better and she has not done any stealing and lying.

Recently, we bought both she and her younger brother (7yrs) Tamiya racing cars.  They raced each other and the brother always win.  She's unhappy abt losing and sulks.  Last Saturday, while my husband was at work & my son & I were sleeping, she switched her brother's car and claimed that its hers.  My husband got back from work and discovered the switch.  We got very upset 'cos we know differently.  My husband even proved to her that the car was my son's (there's some markings) but she was adamant that she didn't do it.  She kept on crying and kept on insisting that she didn't do anything.  

How is it possible for her to deny that she did it eventhough we've showed her proof of her lying?  How is it that she really believe that she didn't do it?  Is this normal behavior in a 10-yr old?  Could it be that she did it but she totally erase it from her mind?

My husband is very angry and has told her that if she didn't admit and say sorry, he'll not talk to her anymore.  I've told my daughter that I believe her.  I also told her to just admit and say sorry to her father although she never do it.  She got upset and cried saying she didn't do it.  Whenever I asked her she ended up crying and insisted that she didn't do it.  I don't know what to do.  

Please help!

[Kevin Kennedy, Ph.D.]

It's best now to simply move on, and not dwell on this. It's very unlikely that your daughter is actually unaware of what she did. She's simply not acknowledging it to you.

Children generally are untruthful when they are trying to avoid 'trouble'. Give her some consequence for what she did, don't engage in any more discussion or debate about it, have her do something nice for her brother to make up for what she did, and move on.

Absolutely do not refuse to speak to her - this is an immature and unhelpful response. It conveys to her that she'll be rejected if she makes mistakes, and that's not a healthy way to manage the situation.

[momneedshelp12221967]

A related discussion, How to get my 10 yr. old daughter to admit she's lying was started.