Baby Sounds: Cooing and/or Gurgling

Hello mommies, my baby girl is going 3 months this Apr 24. Until now bihira siya mag produce ng sounds from her mouth. kapag naglalaro kami she just smile. I have some friends na kasabayan ko lang manganak and their babies started to make sounds. Like, oohh - ohh, Ahh - Ahh, or a little laugh. I know I shouldn't compare her to them but I am worried na baka may delay problem siya. We are out of town kaya hindi pa kami maka punta sa Pedia niya.