The actress, 49, lost her mother Anna just over two years ago.
Taking to social media, she shared an adorable family throwback photo.
In the snap she can be seen as a little tot next to her brother and her parents.
Tamzin admitted in the caption that these uncertain times have made her miss her mum more than ever.
However, she finds comfort in rediscovering family photos.
She wrote: "I miss my mum so much in these times but when I find photos like this I feel comfort and warmth and so much love. This must be 1974?"
Dozens of Tamzin's fans flocked to the comments. Many sympathised with her loss, as well as complimented her on how much she looks like her mother.
One user commented: "Miss my mum too. You look so much like your mum in this picture."
Another user wrote: "You look so much like your beautiful mum."
A third posted: "You're so like your mom. I know exactly how you're feeling. Sending you love xxx."
And a fourth wrote: "You are the image of her love ....love this pic and you."
Tamzin Outhwaite's grief
In May of 2018 Tamzin announced that she and her two brothers had lost their mother three weeks prior.
She shared: "These two beauties @jakeycakeyy@keswicko and I lost our beautiful mum 3 weeks ago today, suddenly …THE best mum ever."
In a heartbreaking post months later, she wished her mother what would have been a 68th happy birthday:
"And Happy Birthday today to you mummy. Would have been 68... It’s no age to go but let’s have a huge round of applause for the way you lived your life.
"I’m striving to be more like you daily. #birthaytwinsmumandflo #hippyheart."
Last July she wrote of feeling "overwhelmed" by dreams about her late parent.
She shared on Instagram: "Dreaming and thinking about my mum so much at the moment.
"It's overwhelming. I would love just one more hug and a long, hilarious, wise, comforting conversation with her, which ends in her singing 'Hey, you, get offa my cloud'.
"And falling into throaty, husky, fits of laughter when her voice cracks."
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