Patricia Moore -- Australia

An 18 year old baby sitter, she killed three babies, two females of 
16 months and two years and one male of seven years, by suffocation 
and strangulation.  

http://www.redbackwebs.com.au/cufflinks/police/serial.html#Moore

http://www.publicdebate.com.au/cgi-bin/cgimes?issue=1&post=323&c=1615

http://www.aic.gov.au/publications/tandi/ti25.pdf