My son ASD 2.4 has little in the way of imitation skills. He has just learned to nod "yes" and shake "no" (yey!) although he doesnt use them really consistently. He can copy me do things like match numbers etc but can not touch his head if I do or copy any other Gross motor skills. I think he can copy some things with props- bang a drum etc. He can also imitate sounds and sometimes words only when he wants to.
What I would like to know is can you teach imitation skills or are they an innate ability? Im looking to set up ABA soon and a lot of it seems based around this skills that my son doesnt have.
Also I know that PECS and ABA should be compatible because it is from the same principle but how does it work in practise? Are there problems combining them?