On 6 September 1903, Flossy Maud Mary Ann Mogg was baptised in Stalbridge Parish Church, Dorset England. Her birth date was given as 10 December 1897, and her parents as Walter Mogg (Farmer) and his wife Ellen. On the same day, the same couple had 2 other children baptised: Harold Charles (born 2 February 1900) and Violet Ellen (born 16 February 1902).
In total, between August 1890 and July 1908, the couple had 8 children baptised in the same church. Or rather 9 children, because on 6 April 1898, Flossie Maud Mogg (born 10 January 1898) was baptised (by the same Rector). Neither of her baptisms are shown as 'private baptism'.
The birth dates given are close enough that this looks like the same child to me; there's also only one record in the GRO indices for a Flossie Maud Mogg born between 1895 and 1905, and no death record.
The 1901 census shows a single family living in Stalbridge with head of household Walter Mogg and wife Ellen; the children present are the five children that the baptismal records say had been born by that time.
So: I'm pretty sure this is one child being baptised twice in the same church by the same Rector. But why? Did the parents and Rector all forget that they had dipped Flossie once? Is it significant that she acquired the additional names Mary Ann the second time around (she didn't use these names when she got married in the same church in 1919, and no other Mary Ann Mogg appears in the records at Stalbridge). Or is there some ecclesiastical reason for baptising somebody twice in the Church of England?