Since giving birth to her son Eduardo in September, the Instagram feed of Hilaria Baldwin has been filled with adorable baby photos of him.
However, Alec Baldwin's wife, 37, has revealed the "scary" moment her second-youngest child appeared to be having an allergic reaction.
Captioning a photo of her cradling the eight-month-old in what appeared to be a hospital ward, the yoga instructor wrote: "We had a scary experience where Edu had an allergic reaction.
"I don’t know to what yet, but it was one of those horrible moments a parent dreads.
"Doesn’t matter how many kids you have, there are always moments that shake us, as there is no way we can prepare.
"This was after he was better, the vomit on my clothes had dried, and my friend sent a pic to Alec (who is away working) to let him know it was going to be ok."
The mother-of-six, who hasn't confirmed exactly when the incident took place, added: "I was told that expediency in this situation is key... don't wait to see if it gets better. If you find yourself in this situation – just go and reach for help."
Her post has received more than 39,000 'likes', while a follow-up video reassuring fans that her little boy is "better today" has been watched over 33,000 times.
Baldwin has five other children with her husband, actor Alec, 63, who she married in 2012.
They number daughter Carmen, seven; son Rafael, five; son Leonardo, four and son Romeo, two.
The couple also welcomed a daughter, Lucia, in March - who was delivered by a surrogate, six months after Eduardo.
From his marriage to Kim Basinger, which lasted from 1993 to 2002, the Hollywood star also has a 25-year-old daughter, Ireland.
According to the NHS, signs of an allergic reaction in babies include diarrhoea or vomiting, a cough, wheezing and shortness of breath and itchy throat and tongue.
Other indicators may be itchy skin or rash, swollen lips and throat, runny or blocked nose or sore, red and itchy eyes.
Foods that might trigger a reaction include cows' milk, eggs, soya, shellfish, fish, seeds, nuts and peanuts, as well as foods that contain gluten, including wheat, barley and rye.
If you are concerned your baby is suffering from a severe allergic reaction, call 999 and ask for an ambulance.
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