Taking to Twitter, Nina hit back at a negative comment about her hair, which read: "Please do something with your hair. You look a mess! We have to look at you while we are eating our breakfasts, for heaven's sake!"
Posting a screenshot of the message, Nina wrote: "Women who do this to women. Too repulsed by my hair to eat her breakfast, but managing to bang out this vitriol. Apart from anything else I can't bear inaccuracies - I think we can all agree my hair looked [heart hands emoji]."
Naga was quick to show her support for her co-star in the comments section, writing: "It looked fab x."
Nina was inundated with messages from her followers, who rallied around the presenter. One person wrote: "Omg. Your hair was 10/10 just like you! You beautiful human," while another added: "Nina, you look beautiful. You are a very pretty woman. Would she stand in front of you and say that to your face? Shame on her."
Actress Rachel Shenton, who stars in All Creatures Great and Small, also shared her support, tweeting: "The comment says far more about her than it does about your hair! (Which is great btw) xx."
Nina's tweet comes just weeks after she revealed that she and her husband, Ted, are expecting a third baby.
The mum-of-two announced the exciting news in an Instagram post to mark Mother's Day, paying tribute to mothers everywhere and sharing her experience with her third pregnancy so far. She said in part: "I'd like to say 'you got this Mama!' But maybe you haven't. I dunno. It's hard, isn't it? That said we are doing it again."
She went on to detail her symptoms, which include "intense migraines", "anxiety" and "first-time acne".
Nina continued: "I am settling into the middle chunk (emphasis on chunk) and enjoying the wonders of Mother Nature and her tiny kicks and flutters. The boys and the cat have been enjoying their new chair. God willing, Baby Doner-Shish joins the outside world in the summer."
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