There is a birth for a Dorothy E Putland born in Eastbourne in 1913.
Reference:
Eastbourne, March 1915, Vol 2b, Page 122
Interestingly the name given for the mother is also Putland. Perhaps if it is your Dorothy, her mother married a Mr Brinkman so she put that name on her marriage certificate, but used her real maiden name for the birth of your father.
Liz