My 8 month old started to look as if he was going to bum shuffle so to encourage him I put a toy out of his reach. After a few attempts to get the toy he reached for one of his arms on his sleepsuit and stretched it (pulling his hand inside)and then had another go with his new longer "arm". When it wasn't long enough he pulled it harder. After 10 minutes he looked at me as if to say "Mummy I will just have to wait for my arms to grow".