Baptismal transcriptions for that period are very thin on the ground and many baptisms do not show the actual dates of birth - only the baptismal date
Mary appears to have been born in Preston as her birth was registered there in the December qtr 1902 as was Roberts in the same qtr in 1904
Alice and Ann were both registered in the March qtr of the years shown in Preston
These are all the areas covered by the Preston Registration District so you need to narrow down any potential search
http://www.ukbmd.org.uk/genuki/reg/districts/preston.htmlBaptisms could take place weeks, months or even years after a birth - and sometimes not at all so it would require a physical search of the parish registers
What religion were the family
Where were they living in 1911
