Parents are being advised not to allow young children to play with “crystal babies”, which may be dangerous if they are swallowed.

“Crystal babies” are made from a jelly-like substance which expands when it absorbs water and has some characteristics of a toy. They can be dangerous to young children if swallowed.

The advice was posted on the Facebook page of Kat Kattaleeya, a mother whose child, Nakhun, had to undergo surgery to remove a “crystal baby” which he had swallowed.

Kat said in her post that her son vomited frequently and could not eat anything, so she took him to see a doctor. The doctor did a CT scan and found something blocking his intestine, which required immediate surgery.

She said that the substance blocking the intestine was a “crystal baby” or water bead, which was about 3cm in diameter. She added that the boy is now recovering in the intensive care unit.

She admitted that she allowed her boy to play with the water bead, not expecting that it could endanger his life.

Her post was shared on the Drama-Addict page, with a warning to parents not to keep “crystal babies” around the house, if it contains young children, and criticism of some YouTubers for promoting them as a toy.

The Drama-Addict page also cited a case abroad in which parents bought baby crystals for their 8-year-old to play with, but their 10-month-old baby swallowed one of them and had to be rushed to hospital for emergency surgery.