Jessica Simpson's parents reportedly can't stop arguing about who will walk her down the aisle.

The 33-year-old star, who is set to marry Eric Johnson in Santa Barbara, California this weekend, is stressed out about the tension between her father Joe Simpson and her mother TINA SIMPSON, who divorced last year amid rumours he is gay.

A source told America's OK! magazine: ''It's supposed to be the happiest day of Jessica's life but all the drama is making it a nightmare.''

Tina is allegedly livid with Joe and wants to give her eldest daughter away.

The source said: ''Joe was furious. And Jessica is stuck in the middle.''

Jessica's sister Ashlee is also allegedly upset that she chose her best friend and former personal assistant Cacee Cobb to be her maid of honour, and initially ''refused to be in the wedding at all,'' before she calmed down and agreed to be a bridesmaid.

Meanwhile, the blonde beauty has lost so much weight recently that her wedding dress is now two sizes too big.

The insider added: ''They can alter it. But she has to stop losing weight.

''For her wedding, Jessica isn't happy with slender. She wants skinny.

''The pressure has really taken a toll.''