Ahead of the concert the pair, and some family friends, headed to Buckingham Palace, where they posed outside the gates. Penny completely stole the show with her incredible outfit as she wore a fitted blue coat and a flirty spotty dress underneath. The star made sure to feel comfortable in her outfit as she posed in a pair of black trainers.
WATCH: Penny Lancaster wows in leopard-print outfit
Rod also rocked an eye-catching look, as he stood in a tartan coat and necktie with the most impressive colour combination.
Penny explained the mood ahead of the major event, as she wrote: "Excitement and nervous for Saturday night #partyatthepalace."
However, many fans dismissed the nerves and assured the star that Rod would be fine as they showered the singer with praise.
Rod will be performing at Party at the Palace
One said: "He's one of the best, can't wait to watch," while a second simply added: "Nerves? He'll smash it!"
A third penned: "Go Sir Rod. Can't wait to hear your performance at the Palace celebrations for our wonderful Queens Platinum Jubilee," and a fourth commented: "Wishing you the best of luck, you'll have a fabulous time Sir Rod, and as always be amazing."
Penny is recently back from some time abroad, and while she was away she looked so elegant in a wide array of outfits.
On Wednesday, she rocked a high-cut pair of dungaree shorts with a white T-shirt and posed next to her stepdaughter Renee Stewart, who Sir Rod shares with his ex-wife Rachel Hunter.
Penny always stuns with her outfits
Actress Renee smiled and put her arm around Penny's shoulder, and was also dressed simply in a stylish black playsuit. "Happy Birthday Renee," Penny captioned the sweet picture.
Penny shares two children with Rod: sons Alistair, 16, and Aiden, 11.
Speaking to HELLO! in a previous interview about her blended family, the star sweetly said: "Being a stepmother to start with was very daunting and challenging, but it’s proved to be an honour and very rewarding."
She went on: "When I first met my husband 15 years ago, his youngest was five and the oldest was 21. So I got to see the different stages that children go through and the challenges they hold, but the rewards as well."
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