I was the same with my eldest, we stopped at 6 months.
Now you have to do it until a year, but only the bottle equipment, milk has more bacteria in it than anything else & it often gets stuck in the bottles & washing doesn't get out, thats why we have to sterilise, to make sure all the bacteria is gone.
Bowls, beakers, spoons, ect are all fine, its only bottles!!
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