The discovery comes as the Mother and Baby Homes Commission has called for information relating to the burials of a “large number” of children who died at the home between 1922 and 1998.

An Irish Examiner investigation has uncovered three grave plots in St Finbarr’s cemetery in Cork City which contain the remains of at least 21 children.

The first of these plots is unmarked and was purchased by the now closed St Anne’s Adoption Society. Founded in 1954 by the then Bishop of Cork Cornelius Lucey, it was set up with the purpose of arranging the adoption of babies born to Irish unmarried mothers in Britain. It closed in 2003 and its records are now in the possession of Tusla.

This plot contains the remains of three girls and one boy. Their deaths occurred in 1979, 1983, 1988, and 1990. The plot is unmarked and contains no headstone or any markings to indicate that it is a grave.

In the case of the last burial in 1990, the child’s death certificate notes that while she died in St Finbarr’s Hospital in Cork, she was in the care of the nuns at Bessborough Mother and Baby Home. A birth entry for this child in this name could not be located.

In the case of the three other children buried in the plot, just one has both the birth and death recorded. The other two children have birth certificates but no death certificates could be located in those names. It may be the case that the deaths were recorded in the names of the foster/prospective adoptive parents.

The second plot belongs to the former St Patrick’s Orphanage run by the Mercy Sisters. It operated a nursery for St Anne’s Adoption Society, where children were kept until the society could arrange for an adoption to be contracted.

There are a total of 16 children buried in this plot — their deaths occurring between 1957 and 1978.

This grave is marked but just one name is recorded — that of the final child buried in the plot. The other 15 children in the plot are not named.

Two of these children died in Bessborough in 1976 and 1978, while a third was born in Bessborough but died in St Finbarr’s Hospital. In the case of the other children, a number were born in UK, with others born in Ireland.

The third plot is a non-perpetuity plot — indicating it is unowned. It holds the remains of at least one child.

The death certificate states her death occurred at St Finbarr’s Hospital in 1989 but that she was in the care of “c/o Sacred Heart Hospital, Blackrock, Cork” — the address of the Bessborough Mother and Baby Home.

In 2015, the Irish Examiner revealed 470 infants and 10 women were recorded as having died at the Bessborough mother and baby home between 1934 and 1953.

The Irish Examiner put a series of questions to Tusla on the latest revelations. It stated that, between 1957 and 1990, there were 16 recorded infant deaths in St Anne’s Adoption Society and St Patrick’s Orphanage.

“Records which were accessed indicate that 13 mothers were informed,” said a statement. “This does not mean the remaining three mothers were not informed; records of notification to mothers/family members are not always held on files.”

“All 16 births were officially registered. Fifteen of the 16 deaths were identified as recorded on the Register of Births, Deaths and Marriages. Records in relation to the death of one child were not located.”

In a statements, the Sister of the Sacred Heart of Jesus and Mary said: “As indicated previously all records relating to Bessborough were passed to the HSE in 2011 and are now in the possession of Tusla. We will continue to deal directly with the Commission of Investigation into Mother and Baby Homes on all such matters.”

Similarly, the Sisters of Mercy said that they would “deal directly with this Commission on all related matters”.