Jessica Simpson rented ''a few yachts'' to celebrate her birthday.

The singer and fashion mogul, who turned 35 last Friday (10.07.15), rented a private plane to fly 30 of her closest friends, as well as her husband, Eric Johnson, and mother Tina Simpson to St. Barts for a week to mark the occasion in style.

A source close to the blonde beauty said: ''She rented a few yachts - 'his' and 'her' yachts. The girls were on one and the boys were on the other. They spent the days island hopping.''

The 'With You' hitmaker and her pals enjoyed candlelit dinners with fresh seafood made by a private chef after spending their days snorkelling and riding jet skis during the lavish holiday.

The group also went to a burlesque-themed bar dressed in costumes to mark Jessica's actual birthday.

The insider told PEOPLE magazine: ''She got a lot of sentimental gifts from friends and stuff for her new music studio - and some jewellery and a guitar.''

Aside from working on a new album, Jessica, who has daughter Maxwell, three, and son Ace, two, with Eric, is also gearing up to open her first boutiques in Chicago, Los Angeles and New York ''within a year.''

A source recently said: ''She's so excited! She's always wanted her own stores. It's amazing and is a dream come true.''