Starts between 11 1/2 and 12 1/2 weeks
After this leap, Harvey
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discovered new vocal such as screaming, cooing and crowing
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was more lively and active, squirming and turning in all directions
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clearly showed his emotion when he finds something funny and interesting
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blew saliva bubbles
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shook a rattle
Note: Harvey is in the process off learning how to roll from his tummy to back on his own.