I think it's pretty common for babies to start out straight. Things could definitely change

My first was straight/wavy until about 5 months:


now - after bath -3bc


now - styled:


my second at one month:


now - much tighter curls 3c/4a

mini-album w/ various styles for the past 10 years of natural hair:
http://s29.photobucket.com/albums/c252/wavezncurlz/hair/
password: curlzorwavez