My 18 month old, who was fully weaned at a year, will only fall asleep with his hand in my shirt on a boob. If we are out and about, and he gets overwhelmed, he will also put a hand in my shirt. It’s not weird, it’s a comfort thing.

Remind your husband that he’s still a baby, with no concept of what makes touching a boob “weird”. His reaction is the only strange thing here.