What insect is laying eggs in the upper leaf stems and back of the heads of my sunflowers?

Question

There were protruding deformities near the upper stem and in the back of the heads of my sunflowers. I cut them open and these nasty larvae (some brown, some yellow) were inside these pod-like holes. Some of the younger sunflower heads with these did not develop and there is only an egg/larva pod where the head should be.

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Answer 1

It is, most likely, the sunflower moth. This article will help: https://www.gardeningknowhow.com/ornamental/flowers/sunflower/sunflower-problems.htm

Answer 2

Thanks, BushDoctor. I had been googling descriptions and images for the past 2 weeks. I was thinking Sunflower Midge, but wanted to ask as this is my first time growing sunflowers :) I never saw any caterpillars, but maybe because I cut them off before they had time to mature.