It doesn't necessarily need to be winter for babies to get poorly.
With their still-developing immune systems, our little ones are highly susceptible to coughs, colds, bugs and viruses all year round.
If you're a new parent (and even if you're not), it can sometimes be hard to identify signs - which aren't overtly serious - that your baby needs urgent medical attention.
Back in 2018, mum Charlie O'Brien filmed her daughter, Luna, breathing in a way she'd not seen before.
It followed a day of her mostly sleeping and not crying at all - which Charlie said was unusual for little Luna. After unbuttoning her onesie, she noticed with some alarm how Luna's chest was moving.
In the post which she recently shared Charlie wrote: "When Luna was 4 weeks old she had a really quiet day of sleeping and barely any crying (unusual for Luna!)
"I was watching her sleep next to me and realised it didn't look right. I unbuttoned her babygrow and this is what I saw.
"Sucking in at ribs is a sign to get your baby or child to hospital.
"She had bronchiolitis and her oxygen levels were very low. Luckily after a night on oxygen she made a very good recovery."
Bronchiolitis is a common respiratory tract infection in children under two years old, and it's caused by a virus which effects the bronchioles, which in turn can labour a baby's breathing when they become swollen.
