I have to admit that I'm having a chuckle at the "window of opportunity" concept. I think that BLS is a brilliant approach, but I wouldn't get too tied up with the timing. All is not lost if babies don't get started on solids till after they are 6 months.
I haven't read the book, but I remember DD was SO ready to eat before 6 months, pracxtically grabbed the food from my hands, but I didn't let her because I really wanted her to wait till 6 months. Alas, at 6months, she had no interest at all until 8 months.
However, DS is now 5months and shown no interest at all!
So I say that if your LO shows serious interest, let her go for it. My DD definitely missed her window.
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