our report tonight from nbc's diana alvear. >> reporter: it is a scene all parents can relate to, a screaming child who won't go to sleep. >> we're trying to help you. >> reporter: do you respond immediately? or let them cry it out? writer leah young went through this a few months ago. she was never an advocate of letting children cry themselves to sleep, but with dad out of town, she called her mom for advice. >> she talked me through it. i got off the phone, it was probably ten or 15 minutes total. >> reporter: a new study appears to back mom up. australian researchers tested two sleep-training methods, controls comforting, where parents take longer and longer to respond to the cries, and camping out, where they sit farther and farther away from the crib. years later, they found no significant damage to the kids, nor did they find any increase in depression and anxiety in the parents. >> you can not only help them to sleep better, but you can help the family with the stress they're having. and you will cause no negative impact on the family itself. so it is really a win, win for the family

. >> now news from diana alvear. >> top and america's money, relief at the pump. gas prices should be going down this month. there were at their highest ever for a labor day weekend. much of that was fuelled by a shutdown of oil production along the gulf coast banks to hurricane isaac. organic foods are the fastest- growing part of the grocery market, but a study finds no difference between organic and conventional produce. is a difference in the level of pesticide residue, but it's not significant. it will cost you less to use a layaway program at toys"r"us this holiday season. it is waiving its service fee and a minimum purchase requirements through halloween. after that it will cost $5. the national average from the pituitary is now $3 per tooth. that is up 50% from last year. -- up 15%. there's an application to help parents determine the real value. >> the nationals assured they will have a winning record this season for the first time ever. the recall and the best record in baseball. detwiler pitching right there. adam laroche had a solo home run in the seco

diana alvear is here with more on that. >> reporter: good morning, matt.breath of fresh air, a celebrity mom that admits baby weight doesn't come off overnight. with a support system of family and friends and a little less fried chicken, she'll get there. jessica simpson's pregnancy and weight gain were well documented. paparazzi, a magazine cover, late-night tv. >> we're waddling at this point. and i'm wearing six-inch heels today. it's a lot of weight to carry on six-inch heels. >> now simpson is speaking out about her baby weight, four months after the birth of daughter maxwell drew, shown here on the june cover of "people" magazine. i didn't realize it didn't all come off with the baby, she tells "usa today." the pop star and actress admits it's been a challenge to lose the baby weight. i let myself indulge in everything i wanted because it was the first time i was pregnant and i wanted to enjoy it. >> she's a southern food, she likes fried food and fried chicken. >> reporter: while simpson won't confirm how much she gained, she's getting down to work