I know early introduction of peanuts has been the recommendation for a while now, but I haven't seen such a strong position before on when to introduce peanuts (particularly for high-risk infants):

http://www.nytimes.com/2017/01/05/well/eat/feed-your-kids-peanuts-early-and-often-new-guidelines-urge.html

I think we introduced peanuts pretty early, maybe around 7 months - we'll definitely keep this in mind for #2!