My husband’s family is Nepali and for generations they have used small mustard seed pillows for their baby. You can see them for sale everywhere from Amazon India. My in-laws still have the same land and have passed on cultural practices. I am a white Australian and had heard that pillows were dangerous but I think my husband’s indigenous mountain culture has wisdom we have lost. My husband’s family has gifted a pillow like this for baby and I want to use it but feel anxious because of my Western background. I can’t find any documented case of a baby dying using a mustard seed pillow, only Western-style pillows. Do you know of any cases?

It is difficult to locate information that describes very specific cases like the death of a baby using a mustard seed pillow, but most individual deaths in infancy will be classified as SUDI, SIDS or Fatal sleeping accident. The death reports will often talk about sleep environment including pillow use as a contributory factor.

Sadly, in countries like Nepal (& many other countries) the Infant Mortality rate is close to 10X that of Western countries.
This is very sad, but often difficult to understand.

Red Nose recommends withholding a pillow until baby is at least 2yo & no longer in a cot.
This is because pillows have been associated with an increase risk in Sudden Unexpected Death in Infancy (SUDI - SIDS & Fatal Sleep Accidents)
Babies have been known to suffocate from using a pillow. Also, baby’s head can be “pushed forward” when using a pillow which may compromise their airway.
https://rednose.org.au/article/can-baby-use-a-pillow-to-prevent-flat-head

Most families want to use a pillow to reduce flattening on the head &/or for comfort.
Babies do not need a pillow for comfort & there are many ways to reduce the risk of altered head shape - this includes Tummy Time when awake from birth.
https://rednose.org.au/downloads/RN0407_22_Tummy-Time.pdf

Placing babies for sleep on their back on a firm, flat & well-fitting mattress has contributed to an 80% decrease in SUDI
https://rednose.org.au/article/red-nose-six-safe-sleep-recommendations

https://rednose.org.au/article/grandparents-and-safe-sleeping
https://rednose.org.au/article/how-to-talk-to-your-parents-about-safe-sleep

Is it possible that the mustard seed pillow could be used to help baby doing tummy time when awake?
Some parents use a small pillow or rolled up towel under the chest when baby is doing tummy time.

What is the reason for babies in Nepal using a mustard seed pillow?
These discussions can be very difficult but important.