My child's carseat was purchased in 2012. the seat belt pieces do not stay tightened. they are tightened every time our daughter is put in and are loose by the time we take her out after each trip. this happens without fail every time and has happened from the first time we used it. (related vehicle information: model year=july 2012, make=snugride, model=1809558) (related vehicle information: model year=2007, make=toyota, model=rav 4). *tr