Helpful websites in the area of speech
http://www.quia.com/shared/speech_therapy/
http://www.asha.org/public/speech/disorders/speechsounddisorders.htm
http://www.campbell.k12.va.us/TES/msisk/media/articulationnorms.pdf (this is a chart that has normal sound acquisition)
http://www.asha.org/public/speech/disorders/speechsounddisorders.htm
http://www.campbell.k12.va.us/TES/msisk/media/articulationnorms.pdf (this is a chart that has normal sound acquisition)