The couple's youngest son, Aiden, marked his 10th birthday, and Loose Women star Penny treated her Instagram followers to a peek inside the family's celebrations.
WATCH: Penny Lancaster's son Aiden shows off his favourite Christmas present
Just like his dad, Aiden is a passionate supporter of Celtic FC, and Penny decided to bake a cake in honour of the Scottish football club for the birthday boy to enjoy.
She shared a photo of her incredible creation, which was covered with turquoise and green icing and featured a Celtic-themed topper, which read 'Happy Birthday Aiden'. The cake was also adorned with miniature football players and two white candles to mark Aiden's age.
Penny showed off her birthday cake for Aiden on Instagram
In the background of the photo, a sweet snapshot was also visible, showing both of Penny and Rod's sons in their green and white Celtic kits and appearing to be sat in the Glasgow football stadium. The couple are also parents to Aiden's big brother Aiden, who turned 15 in November.
Penny's second birthday photo showed a stack of pancakes covered in chocolate sauce, bananas and blueberries, as well as decorative white stars.
Both Aiden and Alastair are passionate Celtic fans - just like their dad
The 49-year-old explained in the caption: "Made my first lemon drizzle birthday cake and blueberry, banana pancakes for my birthday boy today!"
While Aiden has clearly inherited his dad's passion for Celtic Football Club, he also shares his mum's love of animals.
Last month, Penny shared a rare video of her youngest son, revealing that she and Rod had given him a hamster for Christmas.
Penny and Sir Rod have been married since 2007
"Aiden's favourite Christmas present," she wrote over the video, which showed her son lying on the floor watching the hamster play inside a paper tube.
"Watch, when she goes back it's so funny to watch, just watch," Aiden can be heard enthusiastically telling his mum, as she films the sweet scene.
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