A third child from one family has been admitted to hospital with suspected botulism after eating curry sauce.
Two of the child's siblings have already been confirmed as having botulism after they were taken to hospital last week.
They had all eaten a Loyd Grossman-branded korma sauce, made by Premier Foods.
NHS Forth Valley said the child is in the Royal Hospital for Sick Children in Glasgow with suspected botulism and that further investigations are being carried out.
The two siblings, from the Forth Valley area in central Scotland, were admitted to the same hospital last week. Their condition is said to be improving.
The health board said the suspected source of the botulism for the new case is the same jar of Loyd Grossman korma sauce used by the family.
The Food Standards Agency (FSA) advised the public not to consume jars from a batch of the sauce, which it has recalled from shop shelves. The recalled 350g jars have a best-before date of February 2013 and bear the batch code 1218R 07:21.
Only one jar from the batch is known to have been contaminated with the bacteria that causes botulism, the FSA said.
TV presenter Grossman is said to be "devastated" by the situation.
The Health Protection Agency said preliminary tests on the used jar identified the toxin that causes botulism. It has notified health professionals across the UK of the situation and advised them to look out for people of all ages with possible symptoms.