My husband and I started signing with our daughter when she was 6 months old. Mostly because we thought it would be cool to have her able to communicate to us at an early age but also because I work in early intervention and I have seen how it helps other children communicate with their parents. Around 10 months she started signing back to us she is now 17 months and knows 15+ signs and has a growing vocabulary with signs and words. We mostly sign what she wants and needs milk, more, medicine, hurt etc. Now that she can associate a sign with a word she is learning much more. My parents have a fire place and I have tried to teach her not to go near it. I her hand close to it so that she could feel the heat and signed "hurt", and said "this will hurt you! Do not touch it will hurt" she knows now that hurt = pain and has not touched it at all. She has suffered some medical problems and even though she does not have the verbal words she has been able to sing to us that her head hurts and she needs medicine. It has been such a blessing to have her be able to communicate to us what she wants. She amazes me at how smart she is... she will hear my phone ringing in my purse she will come sign to me "phone" and say hello to let me know I need to go answer it. She will point out animals that she sees when we are driving and sign them.
I tell my families that I work with every family has to do what is best for them. And signing has been an amazing Blessing to my family. Instead of her screaming that she wants something she will come sign to me and we have way less temper tantrums then most of my friends children her age. My parents and in-laws can not understand alot of what she is saying yet. Example she says "wa" for water but she will sign milk along with it and they know she needs a drink. We are now working on signs for potty training and she will already sign when she has pooped and needs changed she is only 17 months old!!! We fully plan to sign with the rest of our children.